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Car Craft's Giant EFI TestWritten by Jeff Smith on February 6, 2014 Contributors: Ed Taylor We Test Four Self-Learning Throttle-Body EFI Systems on a Rat-Motor Nova
Electronic fuel injection has come a long way in the last 30 years. Early aftermarket systems were complex, slow, and the user had to combine the unique talents of computer software user and accomplished engine tuner. The duo of high price and complexity kept all but the heartiest car crafters away. When the first adaptive systems came on the scene several years ago, many were skeptical, but these systems have now had the benefit of experience to become, for the most part, the simple-to-use-and-install systems they are advertised to be. We decided that what the world needed was an unbiased test of each of the four most popular systems to see just how easy they are to install and whether they can indeed deliver on the promise of better driveability and maybe a mileage improvement, too.
The four self-learning EFI systems we chose to evaluate are the MSD Atomic, FAST EZ-EFI 2.0, Edelbrock E-Street, and Holley Terminator EFI. All of these systems use a dedicated, standard 4150 flange throttle body with integrated injectors, making it a simple switch from a carburetor. That part is very easy. However, it is the implementation of a quality fuel-delivery system that is essential to a durable, trouble-free throttle body fuel injection (TBI) system. Our suggestion is to build the fuel-delivery system first and ensure its performance before you tackle the TBI.
This is also a good place to warn that these self-learning EFI systems are not a cure for a worn engine with two cylinders with burnt valves. On the other hand, we all know that most carbureted performance engines tend to run at a rich air/fuel ratio (AFR) nearly all of the time. Our experience with carburetors is that you can tune them to efficiently operate at steady-state levels like highway cruise or idle. The problem is that, unlike a boat, cars operate a majority of the time in transient conditions where the throttle is constantly moving. It is in these transient conditions where EFI can have a distinct advantage over a carburetor. When fitted with a wideband oxygen sensor (WBO2), it becomes obvious very quickly that carburetors suffer from very rich conditions in deceleration. All of the EFI systems we tested maintained a much leaner AFR when the throttle blades were closed and the rpm was descending, while a carburetor tends to nearly flood the engine with fuel. Combined with carburetor tuning that creates a rich condition on acceleration, EFI is probably at its best compared to a carburetor in transient, part-throttle, in-town traffic. We didn't simulate that specifically in our mileage test, but our guess would be that any of these systems would deliver far-superior around-town mileage, showing perhaps 2–4-mpg improvements when compared to a carburetor.
Our EFI test involved bolting on these four, self-learning EFI throttle-body systems to evaluate each in terms of how well they performed on our 496ci Rat '70 Nova test mule. We also evaluated these systems for ease of installation, how easy they were to configure, and how quickly each system could get your car running down the road with a feedback, self-learning fuel-injection system. That part was pretty easy because all of these kits performed equally well, a couple better than others in one particular test. Overall, the simplicity of the designs is what makes them attractive.
The reason for this simplicity is that in the past the end user had to create his own base fuel (and spark) maps. This first required a laptop computer along with a rather large knowledge base of engine fuel requirements at different engine speeds and loads, and knowledge of how to make all that work within the limitations and complexities of the EFI system's software. Even among the least-expensive EFI programs (like MegaSquirt), configuring the system demands specific software, computer, and engine expertise. Conversely, these newest, self-learning systems do not require a laptop, and anyone with newbie engine knowledge can program the simple inputs necessary to make the system work.
So while some may rant against the complexity of technology, here is an example of how the technology makes things easier and still delivers excellent performance for a reasonable cost while minimizing the technical expertise. We bolted each of these systems on our big-block and within a few minutes of completing the installation, we were driving down the road enjoying excellent throttle response.
As we completed the testing on these systems, everybody had the same question: "Which system is the best?" We think the answer depends upon what you want. That's not the question-dodging politician's answer that it sounds like. Instead, all four of these systems performed very well (with a couple minor hiccups), so from a performance standpoint, we would not hesitate to recommend any of these systems for the average sub-500hp street car. So then the question becomes less about performance and more about options or opportunities that one system offers that the others don't. As an example, if upgrading to a more sophisticated EFI system down the road is very important, then the Holley Terminator system offers great potential for expansion. If your plan is to bolt on an EFI kit and never touch the engine again except to change the oil and plugs once a year, then the least-expensive kit is probably the best. If you are an electronic geek who is attracted to the idea of an Android tablet included with the EFI system, then Edelbrock's E-Street system might be worth the price. If appearances are important, the MSD Atomic has by far the smallest, least-obtrusive wiring harness, since the ECU is integrated into the throttle body. And if your carbureted big-block already makes 800 normally aspirated horsepower, or you like the idea of converting to E85 fuel, then the EZ-EFI 2.0 is the only choice. We could go on, but you get the point. This test is perhaps the most complex we've taken on because of the dozens of similarities and variables across these four systems. We've done our best to illustrate as many ideas and opportunities as possible, but declaring a "winner" is something that only you can do. That's the beauty of being in this situation—you have four clear choices and you really can't make a bad decision. So let's get to the details.
Test Mule
When it came time to evaluate these TBI systems on our 496ci-powered '70 Nova test car, the old saying, "Beat it like a rented mule," became a war cry. We first assembled the Nova to test electronic overdrive transmission controllers ("In Control," Mar. '12) using the 496 we flogged for our big-block oval-port cylinder head test in the Mar. '08 issue. That combination made 590 hp and 620 lb-ft of torque with a set of Brodix oval-port heads and a mild Comp hydraulic roller camshaft. Next, we plugged in a boneyard refugee 4L80E with a TCI lockup 10-inch torque converter and finalized the drivetrain with a Currie-built 3.55:1-geared limited-slip 9-inch Ford rearend. We bolted on a set of P275/40R17 Toyo Proxes R888 soft-compound tires on a set of Weld Racing wheels and then discovered we needed a set of Competition Engineering Slide-A-Link traction bars to keep the rear tires firmly in contact with the pavement. We also previously had installed a Rick's Tanks stainless steel fuel tank with a Walbro in-tank electric pump that was capable of feeding our voracious Rat. With that, we were ready to take on these four TBI fuel-mixers.
The hardest part of installing any EFI system is building the fuel-delivery system. We've covered that in another section of this story. The next step is much easier—installing the WBO2 sensor. It's important to locate the sensor in the top half of the exhaust pipe to prevent cold-start condensation from possibly damaging the sensor. All of the kits supply a bung that is not difficult to install but does require welding. Make sure that the upstream portion of the exhaust leading to the WBO2 sensor is leak-free. This is critical to ensuring the WBO2 sensor works properly. With this accomplished, the only challenge left is finding a suitable home for the ECU and routing the wiring.
Unpacking a TBI box might be slightly intimidating because of all the wiring and connectors, but don't let it get to you. The connections are all pre-terminated, and each sensor has its own dedicated connector. You can't get them confused because they will only connect to the proper sensor, and each is labeled. There are roughly 10 sensor hookups to perform along with full-time 12-volt power and ground and a switched 12v trigger wire. You'll hear this more than once in this story, but it is essential that the constant 12-volt connection be hooked directly to the battery to minimize electrical noise. Hooking the wires to the battery uses it as a kind of filter or capacitor that minimizes electrical feedback that can otherwise cause untold ECU problems. Make sure that the switched 12-volt power source is live even when the engine is cranking. If not, the engine will probably not start. We chose to build a separate insulated terminal-fed power from a relay that offers system voltage whenever the ignition switch is turned on.
This may sound like we've over-simplified the process, but not really. You will still need to read the instructions. But the main thing that will require some installation time is professionally routing the wires. We'll admit that in the rush to install each of these systems, we just zip-tied each ECU wherever it was convenient because it was going to be quickly replaced by the next box, so we don't have a true installation time. Our best estimate would be four to six hours, not counting the fuel system. We installed the Phantom pump assembly in roughly three hours with an additional two hours to route and install the second (return) fuel line. So any of these system installations could be accomplished in a weekend. Ed Taylor helped us install a first-generation EZ-EFI in roughly 10 hours on our '65 El Camino, including the Phantom fuel system. We did cut a few corners on the ECU wiring that will need to be addressed, but you can use this as a guide.
Fuel Delivery
The underlying truth behind any EFI system is the fact that it will only be as good as the fuel-delivery system. So in order to be EFI successful, you must provide a qualified fuel-delivery system. There are several ways to approach fuel delivery, but based on our 25-plus years of experience with EFI systems, there's really only one way to go. We don't have the space to go into why a return-less system could work or the several reasons why an externally mounted pump is not the best idea for a typical muscle-car fuel system. Let's just cut to the chase and declare that if you really want your EFI-fed car to run properly in all conditions, do yourself a favor and follow our lead.
We've written perhaps a dozen stories over the years on fuel-delivery systems. Each of the four TBI manufacturers has its own fuel pump and delivery system because they have to give you that option. The key to a quality delivery system is an electric high-pressure pump that's capable of continuous fuel flow at 43- to 60-psi fuel pressure, do this with a minimum of noise, and finally to be robust enough to provide years of service with minimal maintenance. Any good fuel-delivery expert will tell you that this requires an inline, in-tank fuel pump. Inline pumps actually pump fuel through the inside of the pump around the spinning armature. This keeps the pump cool. Mounting the pump inside the fuel tank immerses it in fuel, which further enhances cooling. An in-tank pump uses the weight of the standing column of fuel to push it into the pump so it does not have to work to draw the fuel into the pump. External pumps must create a low-pressure area (which can cause vapor lock) when required to draw fuel vertically. Pumps are much better at pushing than pulling fuel. Externally mounting a pump in a muscle car usually then uses the stock fuel tank pickup. The problem here is that when the fuel level drops, fuel slosh during acceleration or cornering uncovers the pickup, fuel pressure drops, and the engine hesitates or bogs. This can work as long as you keep the fuel level above half full, but frankly, that's lame. There's a better way.
We've seen several ideas over the years for in-tank electric pumps and most of these are good systems, including the Rick's Tanks version we are using in our Nova. But, as in the Rick's Tanks case, it requires the use of a custom and sometimes stainless steel tank that can be expensive. In 2012, Steve Matusek, president and owner of Aeromotive, introduced the Phantom fuel-delivery system. This system uses a highly efficient turbine pump located on a stand that positions it just above the floor of your existing fuel tank and returns the fuel to the same location. The pump is surrounded by fuel cell foam with a small plastic bucket at the bottom that retains fuel around the pump. This is by far the most efficient, compact, and affordable fuel-delivery system idea we've ever seen. This is what you should use for a fuel-delivery system. Our recommendation is to purchase a basic TBI kit without the fuel-delivery system. Install the Phantom Aeromotive system and enjoy a trouble-free package.
An exception to this would be if you were going to max out the horsepower potential of the FAST EZ-EFI 2.0 at 1,200 hp. In that case, FAST offers a complete in-tank fuel pump kit (without a reservoir) under PN 307501 that FAST says will support as much as 1,900 naturally aspirated horsepower at 43 psi.
We've installed the Phantom system in a '65 El Camino in a previous story ("The Phantom Knows," Oct. '13) fitted with an EZ-EFI I TBI and tested the system by pushing the fuel level down to less than two gallons and experienced no surging or fuel-delivery hiccups. You should be able to sit on a hill with the engine idling with barely a couple of gallons of gas and not worry about the engine dying due to lack of fuel. That would be impossible with a stock tank using an external EFI pump because the fuel pickup would be sucking air. The Aeromotive Phantom system (PN 18688, $549.97, Summit Racing) is capable of delivering 340 liters per hour, equating to 90 gallons per hour, which Aeromotive conservatively rates at 825 EFI normally aspirated horsepower. This is more than enough fuel to feed any of the systems we've tested, except perhaps the EZ-EFI 2.0's at maximum horsepower potential. We'd also recommend a return-style regulator to complete the fuel-delivery system. We've built many EFI systems over the years and evaluated many others. The Phantom is the best EFI fuel-delivery system for a muscle car that we've ever seen. If you don't have the money to spend on a good fuel-delivery system, then you should ask yourself why you are spending $2,000 on EFI only to cheap out on the most critical component in the entire system. There's a reason that the OE companies all use in-tank fuel pumps for their cars. You should, too.
Configuring the ECU
Each EFI system requires specific inputs to configure the ECU to your particular application. These processes are usually called Calibration Wizard or Setup Wizard. The process follows a similar path—just not in this exact order. The first input is generally engine displacement. In our case, we input 496 ci. All but the EZ-EFI 2.0 also want a camshaft input. Some are more specific than others, but most rank the cam based on intake lobe duration numbers generally in categories of Stock, Mild, or Race. The Atomic system actually warns in the instructions that if the camshaft is more than 250 degrees of duration at 0.050, you shouldn't use this system. This is because intake manifold vacuum will be so low that the system would have difficulty working within those parameters. This is one reason why we chose to test these systems on our 496ci Nova, since our idle vacuum barely achieves 8 inches, which tends to tax the software design, as opposed to installing this system on a 350ci small-block with a mild cam that idles at 16 inches of manifold vacuum. After the camshaft, idle target rpm is another common input. This is essentially commanded idle speed. Keep in mind that if the IAC count on any of these systems is very low yet the engine speed is still too high, you may have to mechanically adjust the idle speed on the throttle body.
Rev limit is generally the next input these systems require. Because ignition control might not always be available, the systems use fuel shutoff to control engine speed. Keep in mind that this does not control mechanical engine over-speeds such as downshifting from Third to First at high speed. Some systems may also ask you the type of ignition you are using—either stock or capacitive discharge.
Other commands that you will need to set include the desired idle, cruise, and wide-open throttle (WOT) AFRs. We set our big-block up to idle at 13.9:1 with a similar air/fuel for cruise and a WOT AFR of 12.8:1. With these simple few inputs into the system, we were ready to rumble. If it sounds simple, it's only because it is.
The key feature of all these systems is what is called Self-Tuning. Let's use the commanded idle air/fuel ratio and idle speed as an example. To start, you command the speed you want the engine to idle and the AFR you want. Given the size of the engine, the injector size, the fuel pressure, the manifold pressure, and about a dozen other variables, the ECU estimates the amount of fuel required to deliver on those commands. The key is the feedback supplied by the WBO2 sensor. The oxygen sensor reports its readings to the ECU. The report will be that the AFR is either too lean, right on the money, or too rich. The ECU quickly computes the difference between commanded and actual and sends a new injector pulse width, and the process starts all over again. This is called closed-loop control. It only takes a short time for the ECU to narrow down the parameters, which is why it didn't take long for each of these systems to learn the basics necessary to make the engine run really well.
The critical point here is that by the stroke of a few keys you can create a system that runs exactly as you commanded. This kind of tuning requires days with a carburetor or hours with older EFI systems. All of this is predicated on the performance of the oxygen sensor, but the technology involved with wideband oxygen sensors has improved so much in the past few years that this kind of dependable performance is possible and all without having to earn a degree in computer science.
System Overview
|MSD Atomic
|Edelbrock E-Street
|Holley Terminator
|Price: Summit Racing
|Throttle Body
|CFM Rating
|Manuf. Claim HP
|No. Injectors
|Fuel Press. Sensor
|Wet N2O Upgrade
|Handheld Screen
|Color Touch Screen
|Fan Control
|Rev Limiter (fuel)
|Timing Control
|No. Pages in Manual
|Software Upgradable
|Laptop Required
Each of these closed-loop EFI systems operates in a similar manner. The ECU measures the critical engine parameters and creates a fuel-delivery schedule based on the inputs from the sensors. Most of these sensors are located on the throttle body itself, making the connections easy since they can only be attached to their intended sensor. So you can't screw up. The following are definitions for each sensor so you can see how each measures a certain engine function.
MAP (Manifold Absolute Pressure): Each of these EFI systems operate under Speed Density. This system assumes a certain level of volumetric efficiency based on displacement and creates a base fuel map that then establishes the amount of fuel delivered to the engine, given by its position on the fuel map, which is based on rpm and load. The MAP sensor converts the manifold vacuum level into a zero-to-5-volt signal to the ECU so it knows how much load the engine is currently experiencing.
TPS (Throttle Position Sensor): This simple device is much like a rheostat that converts the motion of the throttle into a zero-to-5-volt signal that tells the ECU how far the throttle is opened.
IAT/MAT (Inlet Air Temperature/Manifold Air Temperature): This sensor converts the inlet air temperature into a zero-to-5-volt scale, which helps the ECU to decide whether to richen the mixture when the air temperature is cold or make it lean when the air is hot.
CTS (Coolant Temperature Sensor): This converts engine temperature into a scale that the ECU uses to trim mixture.
IAC (Idle Air Control): This is actually a stepper motor controlled by the ECU that is used to maintain idle speed. When the engine is idling, generally a small amount of air is bypassed around the throttle blades through the IAC to maintain the commanded engine idle speed.
FPS (Fuel Pressure Sensor): All these systems use an FPS to monitor fuel pressure because this is critical to flowing sufficient fuel through the injectors. All of these systems are designed to operate between 43 and 60 psi.
RPM (Revolutions Per Minute): This is a critical input into the ECU since all the fuel and driveability programs are based on engine speed. Systems like the EZ-EFI 2.0 require a signal conditioner to establish a good signal to the ECU when using an HEI distributor.
WBO2 (Wideband O2): The wideband oxygen sensor is the critical feedback sensor used to help each self-learning system to adapt to the individual requirements of each different engine. The sensor actually measures the amount of free oxygen in the exhaust and calculates an air/fuel ratio from that measurement. This is why it's critical to seal any leaks in the exhaust system to minimize inaccurate (lean) O2 readings.
Fuel Mileage
Our fuel mileage test constituted the same, mostly highway, 105-mile loop that included one 15-minute stop to test for heat soak starting and roughly a dozen stop lights. To make the mileage test fair to the carburetor, we spent an afternoon (hours longer than it took to configure any of the EFI systems) tuning the Holley until we could get roughly a 13.9:1 air/fuel ratio at our 65-mph cruise speed. Had our test involved much more stop-and-go driving, the carburetor mileage would have suffered dramatically. As a side note, getting 14 mpg out of a near-600hp 496ci is pretty damn good. The 4L80E overdrive with the TCI lockup converter was a major factor. Our highway mileage rpm hovered around 2,300 rpm, and we commanded 13.9:1 air/fuel ratio for all four tests. We didn't try a leaner air/fuel ratio, but it's possible that we might have been able to wrestle even better mileage with a leaner AFR.
|MSD Atomic
|Edelbrock E-Street
|Holley Terminator
|Holley 950 HP carb
|14.4 mpg
|14.2 mpg
|14.2 mpg
|14.5 mpg
|14.2 mpg
Holley Terminator
So what makes the Terminator a possible best buy? What intrigued us was the ability to upgrade. Holley doesn't make a big deal of this, but the Terminator ECU is exactly the same as the one you buy for the HP or Dominator systems. This means that everything the Dominator system offers can be achieved by upgrading from Terminator. This means you don't have to sell your Terminator system if you later decide to add multi-point EFI or go to a multi-stage nitrous system. You do have to purchase additional wiring harnesses, but all the software is already there. Did you know that you can even control a 4L60E or 4L80E electronic overdrive transmission with the Dominator? If expandability is important to you, the Holley offers loads of potential.
Within the areas a handheld unit will give you access, Terminator offers plenty of additional tuning abilities. Under the Advanced Tuning category, you have multiple area access. We didn't have to go into them to allow our engine to run properly since the stock tune was very good, but it's comforting to know that the access is there should you want to perform a little fine-tuning. One example is that the rpm activation of closed loop is set to zero, which means the Terminator runs in continuous closed loop. But the system does offer the ability to increase the rpm to perhaps 1,500 to compensate for big overlap camshafts. The problem with big cams is that free oxygen from valve overlap enters the exhaust system and fools the WBO2 sensor into thinking the engine is running lean. Removing the closed-loop idle fuel control would allow you to manually tune the idle AFR to improve idle quality.
Another area where we found a significant difference was on the working end of the throttle body below the blades. Holley introduces fuel into the engine both from the large discharge hole directly below the injectors but also from several small holes drilled into the circumference of each throttle bore. The idea is to introduce fuel from multiple locations, especially at low throttle openings to enhance driveability.
Terminator also offers ignition control, should you want to integrate digital ignition control with the fuel. This offers advantages such as digital control over the timing curve that allows you to create a more specific timing map based on load and rpm. One way to simplify this conversion on a small- or big-block Chevy is to use the small-cap HEI-type distributor. The advantage here is these distributors are inexpensive and easy to find either used or new. On the Ford side, the system allows you to use a Ford TFI distributor. For our test, we retained our current MSD ignition system on the big-block so that the ignition remained the same for each TBI test.
Atomic EFI
Atomic is one of the latest iterations of the integrated throttle body fuel injection. The Atomic can accommodate any engine from 100 to 800 ci, with its only limitation being the injector output, which is limited to around 650 hp. This means that at 43 psi of fuel pressure the Atomic could easily supply fuel to a small 215ci Olds all-aluminum V8 as well as a monster 500ci Cadillac. Just as we were finishing this story, MSD announced an upgrade that now makes the Atomic compatible with both nitrous- and boost-ready supercharger packages. At press time, we didn't have any details on what makes the system boost-ready. The key with any claim is to look at the fuel flow potential of the injectors and compare them with the fuel required for your application.
As you might imagine, the Atomic will certainly allow ignition control if you so choose. A big advantage would be eliminating the archaic factory mechanical and vacuum advance mechanisms to allow non-linear tuning capabilities. If nothing else, you can do in a few keystrokes what used to take all afternoon to configure mechanical and vacuum advance curves. We did not integrate the ignition in our test, but it's reasonable to expect that we probably could have improved our fuel mileage by experimenting with the digital ignition curves, especially on the vacuum advance side.
The Atomic performed admirably feeding our 496ci, 590hp Rat. The driveability was excellent, and the fuel mileage was right there with the other systems, making this newest system an equal player among the four.
Edelbrock E-Street
When each of the TBI systems delivers similar benefits, it can often be the little things that can set one system apart. The Edelbrock E-Street's most notable feature is a large, 7-inch touch-screen Android tablet that offers Bluetooth wireless connection to the ECU. The tablet is not just essential for the initial setup but can also be configured as a gauge display. The wireless feature is attractive because it eliminates unsightly wires and allows user freedom to use the tablet apart from the vehicle. Plus, the tablet includes an antenna that allows it to be GPS-enabled by downloading software that will display vehicle speed. Even better, it also has Internet connectivity (Wi-Fi) for other tablet uses that have nothing to do with EFI. You might even consider permanently mounting the tablet in the dash. One small point was that our Android's battery life was shorter than anticipated.
If the number of pages in the instruction sheet is any indication, Edelbrock might be among the easiest to install since the EFI portion of the instruction manual is only 23 pages long. There is another 17 pages for the tablet, but even that only totals 40 pages. We configured the E-Street system in short order, and it quickly allowed us to start the engine and the big-block settled very quickly into an orderly idle. Our big camshaft (with 8 inches of manifold vacuum in gear) was no problem, and with our 4L80E in Overdrive, the E-Street delivered excellent light-throttle response, and quick stabs on the throttle to WOT were met with instant response. Overall, the only problem we encountered was in the cold-start test. For our 496ci engine, the E-Street delivered way too much fuel, requiring us to keep the engine running at 2,000-plus rpm for the first 45 seconds of operation before the engine began idling on its own. The problem was an over-rich, cold-engine enrichment program that unfortunately is not user-adjustable. Since the E-Street was the last of the self-learning systems to appear on the market, it's possible that feedback to Edelbrock from our experience will result in a software upgrade in the near future that will address this issue.
The most overwhelming fact about the EZ-EFI 2.0 system is its larger capacity. FAST has rated this throttle body with fuel flow potential to feed 1,200 hp. This is accomplished by including eight injectors compared to only four in the other systems. So if your engine has the potential to make 850 hp or more, the EZ-EFI 2.0 can handle it. Our first question concerned using this same monster TBI on a really tiny engine, such as a 4.8L (293ci) LS GM engine, for example. Controlling eight, 74-lb/hr injectors at idle on a small engine demands extremely short duty cycles that will cause control issues. FAST compensates by staging the injectors to fire only four at a time, which solves the dilemma. The advantage of these larger capacity injectors is that even at 850 hp the system is operating at a very comfortable injector duty cycle. So if big power is in your future, the EZ-EFI 2.0 can handle it.
While technically a different system, FAST also offers a separate kit called a multi-point upgrade that allows the use of the EZ-EFI 2.0 ECU with a multi-point fuel-injection system. So if we had an intake manifold with an injector in every port and a large throttle body upstream, we could control it all with self-learning EFI just like the TBI system. The advantage is the retrofit system is much less expensive than the TBI system (PN 30404-KIT).
Our experience with the EZ-EFI 2.0 was extremely positive. It did everything we asked it to do every time, and with its massive fuel potential, it's capable of even feeding a high-horsepower E85-fueled engine. If we had more time, we would have really liked to test this option.
Professional Products Powerjection III
We originally intended to test the Powerjection III unit because it also is a self-learning EFI throttle-body system. But that was until we opened the box and began reading the instructions. One of our criteria for this test was the fact that you could load the entire system on the car without the need for a laptop. Unfortunately, the Powerjection III requires a laptop to load the software into the computer, which it then imparts to the ECU that is integrated into the throttle body. From reading the instructions, we were going to have to make several critical changes to the base fuel program in order to create a usable package for our big-block Rat motor, since the software was designed for a 350ci engine. This complexity and the requirement for a laptop computer led us to not attempt to test the Powerjection III. It does appear to offer all of the basic amenities of the other systems, and it is also about $400 less expensive than the least expensive of our test systems.
Cold Start
Here's the only area where we discovered minor difficulties with a couple of the systems. Since this is more of a subjective evaluation, we decided to grade the systems on a 1-to-10 scale with 10 being best. Because we don't have access to a freeze room and we live near the ocean, our so-called cold-start is questionable since the coldest temperatures were in the mid-50 degrees F. With each system, we merely turned the ignition on to cycle the fuel pump, waited a few seconds and then tried to start our big 496.
A couple items are worth discussing. It's entirely possible that colder temperatures would produce different results. Unfortunately, cold-start is not a tuning function in some of the systems, although the EZ-EFI 2.0 offers access and the Holley at least gets you in under the "after start enrichment" category. If we hook a laptop up to the Terminator (which you can do after upgrading the software), the Holley instructions do give a simple procedure for tuning the cold-start, which is welcome.
The EZ-EFI 2.0 performed the best with a subjective score of 9 out of 10. This did require us to wait the two seconds necessary to allow the ECU to command the prime circuit, and you can actually hear the injectors cycling. If you encounter a problem, the EZ-EFI 2.0 allows you to modify the cold-start parameters, which is an improvement over the original version that was not user-adjustable. The Holley system does not require you to wait on startup and quickly settled into a stable idle. When we revved the engine once, it stalled on idle recovery, but immediately re-started without hesitation. We gave the Terminator an 8 rating.
The Atomic on cold-start was nearly as good as the other two with a stable idle and no hesitations on acceleration and no stalling. We gave it an 8 only because it was slightly richer than we would prefer. The Edelbrock cold-start test was problematic in that while the engine started easily, we had to manually maintain a 2,000-rpm engine speed to keep the engine running. Once the engine built some heat, the idle stabilized, and everything was fine. The reason for this was because our WBO2 sensor indicated a very rich mixture around 10:1 AFR. In speaking with the people at Edelbrock, they are aware of the problem and offered to alter our software to compensate. Because of this, we gave it a 6 for just the cold-start section. We expect that by the time you read this, Edelbrock engineers will have improved the cold-start program to minimize the excessively rich AFR.
HP Claims
In all these systems, the power limitations are not based on airflow but rather restrained by fuel flow of only four injectors. This is probably why FAST decided to up its game with the EZ-EFI 2.0 by doubling the injector count to eight injectors. FAST could have made the injectors smaller but instead sized them at 74 lb/hr. We decided to do the math on all these systems to see how the hp claims compare to the formula. The basic formula is:
Injector size x 0.85 (85 percent duty cycle) / 0.50 BSFC = hp per injector
There are several variables in this formula that require explanation. First is the duty cycle; this industry standard is intended to avoid running an injector at more than 85 percent of the time to improve injector life. A 100 percent duty cycle means the injector is open all the time, which leads to overheating and eventual failure. The second variable is the brake-specific fuel consumption (BSFC) number. This represents the number of pounds of fuel the engine burns (at WOT) per horsepower per hour. The industry standard is 0.50 lb/hp-hr. We've seen many dyno tests with engines now performing in the 0.45 and even 0.40 range at peak torque. These lower BSFC numbers are typical of today's current crop of Ford Mod, GM LS, and Chrysler Hemi engines that burn less fuel to make the same horsepower compared to older engines.
Another variable affecting injector output is fuel pressure. Any injector rating in lb/hr must include fuel pressure for accuracy. Most aftermarket injectors are rated at the industry standard 43 psi (3 bar). An easy way to increase injector output is to increase the fuel pressure from 43 psi to 60 psi. This can improve injector output by 18 percent. We will give you both the manufacturers' numbers and our calculated numbers.
It's important to note that because every engine is different, your BSFC numbers might be better or worse than our estimates. That's one reason why having access to injector duty cycle numbers on the ECU's display is important. For example, if you have an engine that actually does make 550 hp and you command a 12.5:1 AFR at WOT, you can run the engine up to max power rpm and have a friend watch the injector duty cycle on the output screen. If at any point the ECU indicates more than 90 percent duty cycle, you know that your engine needs more fuel to supply the commanded AFR. This does not necessarily mean the engine is running too lean. Experimenting with different AFRs will show if the engine wants more or less fuel. This is why having another tuning aid like injector duty cycle is helpful.
We must also point out that just because some of these systems may not necessarily supply 600 hp worth of fuel at 43 psi doesn't mean they don't perform. Frankly, most of these EFI systems will find their way onto engines making less than 500 hp, in which case all these systems have more than enough injector "head room" to accommodate normally aspirated performance upgrades like better heads or a bigger camshaft.
In the early TBI self-learning systems, no one offered the opportunity to run a nitrous system. With these latest versions, a couple of systems are now compatible. Among the four systems, MSD, FAST, and Holley offer nitrous configurations. The EZ-EFI 2.0 system will work with the classic "wet" nitrous plate–type system, where both nitrous and fuel are introduced into the intake manifold. There is a Nitrous Setup category you can click on that allows you to select the target AFR, as well as a target total timing number. But the nitrous target timing number (effectively a nitrous retard) only works if the ignition is integrated with the EFI package. Otherwise, you will need to trigger a separate nitrous retard.
The advantage of using closed-loop feedback AFR control is that if the additional fuel supplied by the nitrous plate is slightly rich, the WBO2 will indicate this situation and the ECU will immediately respond to meet that commanded AFR. This has the potential to produce a measurable advantage over a straight carbureted nitrous application. This is basically how the Holley system is also intended to be used, but you will have to perform the free upgrade to the HP version of the software, and this will require a laptop. But it's easy—just buy your laptop buddy lunch.
Software Upgrades
When it comes to electronics, we have come to expect that after the device goes out the door, there will be upgrades. The same is true with EFI systems. The ease with which you can do this will depend upon which system you are working with. One thing to keep in mind is that if you do upgrade, any specific changes you made the existing software will be lost, so it's best to track the changes you've made in a written record that will make it easier to input them back into the ECU once the upgrade is complete.
As an example, because the Edelbrock system uses the Android tablet, software improvements might be a little easier since you can quickly access the upgrade off the Internet and then load it to the ECU. We watched a short video by MSD that showed how to upgrade the software, which involves removing the micro-SD card from the ECU, purchasing an SD card reader, and then accessing the new software from Atomic's website to upgrade the card using the reader. The Terminator system is designed so that a laptop is not needed. However, if you desire to go into the system to make changes that are not currently allowed, Holley engineer Doug Flynn told us that with a laptop and an inexpensive USB cable you can download the Holley V2 software into your laptop and then use that to upgrade the Terminator system. The EZ-EFI system also accommodates updates via the Internet. In all cases, should the manufacturer come up with software improvements, all it takes is a relatively simple upgrade to bring your older system up to date. That's the beauty of electronics.
Throttle Body Horsepower Potential
|MSD Atomic
|Edelbrock E-Street
|Holley Terminator
|Injector Size
|80 lb/hr; 43 psi
|63 lb/hr; 43 psi
|74 lb/hr; 43 psi
|80 lb/hr; 43 psi
|Number of injectors
|Manf. HP Claim
|Calc. HP 43 psi 0.50 BSFC
|Calc. HP 43 psi 0.45 BSFC
|Calc. HP 60 psi 0.50 BSFC
|Calc. HP 60 psi 0.45 BSFC
|Inj. Duty Cycle Display
Parts List
|Competition Eng. Slide-A-Link
|Summit Racing
|RacePak IQ3 dash
|Edelbrock Universal Reservoir
|Summit Racing
|Aeromotive Phantom system
|Summit Racing
|Aeromotive bypass regulator
|Summit Racing
|FAST in-tank fuel pump kit
|Summit Racing
|FAST retrofit kit
|Summit Racing
|Pro. Prod. Powerjection III
|Summit Racing
|Dominator display screen
|Summit Racing
More Photos From This Article View Slideshow
Edelbrock offers an interesting option for fuel delivery. The Universal Fuel Reservoir kit (PN 3605) is a small, self-contained fuel tank that can be mounted in the engine compartment where you can feed it fuel from even a stock-type mechanical pump. Internal in the reservoir is a float system and an in-tank electric pump that can deliver a constant 60 psi of fuel pressure.This is the only part of the Phantom system that extends beyond the top of the fuel tank. The three openings are for fuel outlet, fuel return, and a vent. Phantom also allows retention of the stock fuel level sending unit.A competent return-style fuel pressure regulator is essential to a properly designed fuel-delivery system. All these systems also work best when fuel from the tank is connected directly to the throttle body then routed to the regulator where fuel is returned to the tank.This is the same throttle body currently in use in NASCAR. Note the annulus groove around the base of its throttle bore and the small annular discharge holes that introduce fuel into the throttle bore from multiple points in addition to the large output hole in line with the injector (arrows).The Terminator offers tremendous potential in terms of expansion, since you can easily upgrade to a multi-point fuel-injection system with the same ECU, add nitrous, integrate complete ignition control, and even go so far as control an electronic late-model overdrive transmission like the GM 4l60E or 4L80E. This becomes what Holley sells as the Dominator EFI system.The Holley handheld is small but gets the job done to navigate around the system for both configuration and tuning.If you are looking for a system that's easy to install, Atomic has this covered since the ECU is integrated directly into the throttle body. Notice the dramatic reduction in wiring clutter and the number of connections in this complete system shot compared to the other systems. This makes routing the rest of the wiring harness much easier and cleaner.If you're more into function than fashion or impressing the kids with fancy digital displays, then the Atomic gets the job done. The small black button at the bottom makes navigating through the system simple. Here, you can adjust the equivalent of carburetor accelerator pump squirt to tune your application if necessary. Our package ran fine once it warmed up, with zero additional tuning required. The self-learning function takes care of those details.
The Edelbrock E-Street system is unique with its large Android tablet display and wireless connection to the EFI system. Edelbrock also supplies a mount, but we think it would be cool to clip the Android into the dash but still allow it to be quickly removed for other uses.The Edelbrock Android tablet display offers the largest screen and looks fabulous at night, but during the day we had glare difficulties. I discovered later that my partner had removed what he thought was the protective cover that was in fact the anti-glare screen.Mounted on the engine, the Edelbrock system is clean and easy to work with, and the air cleaner easily cleared the linkage and fuel lines.Keep in mind that we are testing the latest 2.0 version of EZ-EFI, which is identified by its throttle body that looks a little like a carburetor. The 2.0 version is more expensive but delivers much more in terms of power potential and sophistication—and the fact that it has eight injectors mounted in the throttle body.The EZ-EFI color display is small but very easy to read even in bright daylight. There are three pre-programmed dash layouts you can choose from to display items such as a tach, coolant temp, fuel pressure, injector duty cycle, and battery temperature. You can toggle between all three as each offers different readings.One reason for the large 74-lb/hr injectors is not only for big gasoline horsepower but also to be able to easily convert to E85. Since grain alcohol produces about 30 percent less heat per pound of fuel, this requires more fuel to make the same power. So taking the calculated normally aspirated 60-psi horsepower number of 1,182 and reduce it by 30 percent, you can expect this same TBI to supply sufficient fuel for as much as 825 hp. Of course, this assumes you have a fuel delivery system that's E85 capable and compatible.


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I would be very happy if it covers sequence and series from very basics to advanced. Thanks.:)
The one book I own which is devoted entirely to sequences and series is Knopp's Theory and Applications of Infinite Series. I wouldn't call it advanced, but it contains slightly more than I've ever needed or wanted to know, so I am very happy with it.
Bonar and Khoury's Real Infinite Series is an excellent book on sequences and series of real numbers. There are many examples in the book, but unfortunately no exercises.
Many calculus books have numerous exercises on the basics of sequences and series.
For more challenging exercises and for material on series of functions (like power series and Fourier series), you can try a book like Apostol's Mathematical Analysis or Rudin's Principles of Mathematical Analysis. Bartle's Introduction to Real Analysis, 3rd ed. is also excellent and might be more accessible. Bartle's book also has answers to selected problems. Solutions for the exercises in all three books are available online, if you look hard enough.
Another book that you could look at would be Infinite Series by Earl David Rainville. I used this book as a reference for some basics about infinite products (which as you can imagine is closely related to infinite series) for my senior thesis. I didn't use the rest, but it looked like a good discussion of infinite series going above what is seen in a Calc II class, including a couple other tests for convergence.

subset: commoncrawl


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This site uses the term "gifts" of leave rather than leave "donations" to avoid confusion that can result from using "donor and donate" to refer to both leave donors and organ donors.
The UW organ donor shared leave program encourages and supports University of Washington employees who volunteer as organ donors by allowing them to receive gifts of paid leave from other eligible UW employees to cover the time off work required by the organ donation process. The organ donor does not have to exhaust their accrued paid leave to be eligible to receive and use gifts of leave from other UW employees.
For this program, "organ donation" means donation of a whole organ such as a kidney, or donation of part of an organ or of tissue (e.g., liver). It does not include the donation of blood or blood components that are taken by blood withdrawal. The organ donation process includes pre-donation testing, the organ donation procedure, and recovery.
This program is exclusive to the University of Washington. It is separate from, and not related to, the state-authorized shared leave program. Subject to the requirements described below, all full- and part-time UW employees who hold a leave bearing appointment are eligible to participate, either as an organ donor requesting to receive gifts of leave from other employees, or as someone who gives leave to an organ donor. As with the regular shared leave program, giving leave and receiving leave requires departmental approval.
Non-University of Washington state employees are not eligible to participate in this program.
An organ donor may receive gifts of leave from multiple employees, but may not receive or use more leave than is medically necessary for the complete organ donation process.
Organ donors will be asked to submit health care provider verification of the amount of time off work needed for pre-donation preparation, testing, organ donation procedure, and recovery.
Human Resources processes gifts of organ donor shared leave and requests to receive organ donor shared leave, and calculates the hours to be credited to the recipient. HR notifies the recipient's unit timekeeper to update leave records accordingly. If there are more gifts of leave than an organ donor needs, they will be credited only with the amount of leave that is medically necessary.
Leave that is given but not needed will be returned to the employees who gave the leave in an amount proportional to their gifts.
If you are planning to be an organ donor and wish to request shared leave donations, download and complete your portion of the Organ Donor Shared Leave Request form (pdf-version) and submit it to your supervisor. The department is responsible for completing the form and sending it to your unit's Human Resources Operations Office. Human Resources will send the form to the designated health care provider for verification of the amount of time off work you are expected to need. Human Resources will notify you and your supervisor of the request's approval status.
Download and complete the Organ Donor Shared Leave Giving form (pdf version), and submit it to your supervisor. Your department is responsible for completing the form and sending it to your unit's HR Operations Office. HR will notify you, your supervisor, and your unit's timekeeper of the request approval status and final donation calculation.
If you have been on leave as an organ donor, the University expects that you will return to work as scheduled following the procedure. In the event that your return to work will be delayed for any reason, notify your supervisor and/or departmental administrator. Depending on the circumstances, additional verification may be required.
Librarian Leave Topics


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Fat-Soluble Vitamins
Vitamin D: The Sunshine Vitamin
Vitamin D plays an indispensable role in building and maintaining strong bones and teeth. In fact, vitamin D is responsible for the body's absorption and utilization of the mineral calcium. Insufficient amounts of this key vitamin can lead to serious bone abnormalities, including rickets in children (bones that are soft and malformed) and osteoporosis or osteomalacia (softening of the bones) in adults.
Recently, vitamin D has also received a lot of attention for reasons that go far beyond bone health. Research indicates that vitamin D may help prevent autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, psoriasis, and Type 1 diabetes. It may also be a factor in decreasing your risk for cancer of the colon, breast, and prostate.
Food for Thought
The adequate intake (AI) for vitamin D is given in micro-grams, while the vitamin D in food and supplements is usually measured in international units (IU). The conversion is one microgram = 40 IU.
Food for Thought
Your body synthesizes vitamin D when your skin is exposed to sunlight, but too much sun may also increase your risk for skin cancer, wrinkles, and age spots.
Because of its potential to help prevent these diseases, several experts think we should be taking in a good deal more vitamin D than the current RDA. In fact, they recommend a whopping 1,000 IU per day! This is well below the tolerable upper limit (UL) of 2,000 IU per day, but some health professionals worry that 1,000 IU may still be too much. Remember—vitamin D is fat-soluble, and therefore can be stored in the body where it may build up to toxic levels. Some of the symptoms of excess vitamin D include drowsiness, diarrhea, loss of appetite, headaches, high blood pressure, high cholesterol, fragile bones, and calcium deposits throughout the body (including heart, kidneys, and blood vessels).
Your best bets for getting enough vitamin D:
- Allow yourself 5–15 minutes of unprotected sun exposure on your hands and arms every day (more if you are darker-skinned). Of course, if you have a history of skin cancer, you must talk to your physician before exposing yourself to UV rays.
- Eat foods rich in vitamin D, such as fortified milk, tuna, salmon, and canned sardines and mackerel.
- Take a daily multivitamin that contains 400–800 IU of vitamin D.
Vitamin E (Tocopherols)
Vitamin E aids the formation and functioning of your red blood cells, muscles, and other tissues, and protects essential fatty acids (special fats that are needed by your body). Because vitamin E is found in a variety of foods, deficiency is rare. However, an extreme case of vitamin E deficiency involves wasting of the muscles and neurological disorders. To date, there have been no shown toxic effects from taking doses well over the RDA.
Foods rich in vitamin E include vegetable oils, salad dressings, whole grain cereals, green leafy vegetables, nuts and seeds, peanut butter, and wheat germ.
Vitamin K
Thanks to vitamin K, you won't bleed to death after an injury. That's because vitamin K is essential for normal blood clotting. Current research also suggests that this vitamin might play a role in maintaining strong bones in the elderly. Where do you get this vitamin? Interestingly enough, bacteria that live in your intestines help to make 80 percent of the vitamin K that you need, and the rest can be found in a variety of foods listed here.
A vitamin K deficiency can cause hemorrhaging (uncontrollable bleeding), mainly in newborn infants because their immature intestinal tracts might not have enough bacteria to make this vitamin. In addition, people taking antibiotics might temporarily lose the ability to make vitamin K because the medication destroys all bacteria, good and bad.
Foods rich in vitamin K include turnip greens, cauliflower, spinach, beef liver, broccoli, kale, and cabbage.
More on: Children's Nutritional Needs
Excerpted from The Complete Idiot's Guide to Total Nutrition © 2005 by Joy Bauer. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.
To order this book visit the Idiot's Guide web site or call 1-800-253-6476.


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Danica's best finish with full race at Texas
FORT WORTH, Texas — Danica Patrick's first Sprint Cup race with her new crew chief has to be considered a success. Patrick had her best finish in nine Cup starts this season, finishing 24th at Texas on Sunday and running every lap for the first time. Her No. 10 Chevrolet was the last car on the lead lap in the race won by points leader Jimmie Johnson.


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European PlayStation Store Update for February 26th: Thief, Castlevania: Lords of Shadow 2Written by: / / 1 Comment
There's something for everyone in this week's PlayStation Store line-up, ranging from the fast-paced action RPG Ys: Memories Of Celceta for PS Vita to MercurySteam's Castlevania: Lords of Shadow sequel. Also new this week is Thief from Eidos Montreal, with the new-gen version of this stealth title priced considerably higher than its PS3 counterpart.
Sadly there's no PlayStation Plus content drop this week but SCEE has assured us that we'll hear about next month's freebies later today. In the meantime you can head over here for the rumoured list of Instant Game Collection additions in March.
You can browse through all this week's new releases on the PlayStation Blog or directly on the PlayStation Web Store. Here are some highlights from this week's update:
PlayStation Store Highlights
PS4 Games
• Thief (£59.99/€69.99)
• Basement Crawl (R136/£8.49/€9.99)
PS3 Games
• Thief (R679/£39.99/€59.99)
• Castlevania: Lords of Shadow 2 (£39.99/€49.99)
• Pac-Man Museum (R189/£15.99/€19.99; trial available)
• Tales Of Symphonia Chronicles (R394/£24.99 /€34.99)
• Tales of Symphonia (£15.99/€19.99)
• Tales of Symphonia: Dawn of the New World (£15.99/€19.99)
PS Vita Game
• Ys: Memories Of Celceta (R449/£34.99/€39.99)
PS Vita DLC
• Muramasa Rebirth: Genroku Legends – A Cause to Daikon For (R35/£3.19/€3.99)
Tags: europe, playstationstore, sony, southafrica


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In the news, it has been stated that there will be a fairly large asteroid passing fairly close to Earth soon. I've been trying to find a good observation guide, including determining how bright it will be, with bad luck. Specifically, I want to find out if this is a naked eye visible object, and if so, how to find it. Thanks!
I think you're referring to asteroid 2005 YU55 which is making an approach on November 8.
This article on NASA JPL's Asteroid Watch site gives some details including:
which to me implies that it would not be visible with the naked eye. It's estimated size is 1,300 feet (400 meters).
Another NASA site, the Near Earth Object Program, has better technical information which may help locate the asteroid. Some excerpts:
Don't bother checking exact locations until a few hours before closest passage (on Tuesday evening in North America) because the orbit will have last minute changes. The asteroid is predicted to be around 10th magnitude, but from personal experience with several earlier asteroid passages you will need at least a 10-inch aperture to see it. What has worked for me is to find a small star pattern somewhere ahead of the asteroids position on its track, concentrate on that and wait for the asteroid to move into view. In most cases, the asteroids have been ahead of their predicted positions by about 5 minutes, probably because of acceleration by the Earth's gravity. Good luck!


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Let $(M,g)$ be a smooth compact Riemannian manifold. Is there a link between the convexity of all injectivity domains and the sign of sectional curvatures? For example, is it true that a compact surface all whose injectivity domains are convex (that is, for every $x \in M$, the domain of the exponential map $\exp_x$ is a convex subset of the vector plane $T_xM$) is necessarily nonnegatively curved ?
For a non-injective map like $\exp$, there are many alternative choices of subsets of the domain where the restriction is injective. For a flat 2-torus like $\mathbb R^2/\mathbb Z^2$, one domain for $\exp$ is a square centered at the origin, but there are many others --- any shape that tiles the plane by translations in $\mathbb Z^2$ will do. For $\exp$, there is a canonical for vectors whose geodesics don't reach the cut locus. I'll take this to be your meaning. Is there a standard terminology, perhaps even "injectivity domain" as you used? Even if so, I think it is misleading, so I'll refer to it as the pre-cut locus.
Consider the case $M^2 = \mathbb {RP}^2 = S^2 / \pm 1$. For the standard round metric, the pre-cut locus is the disk of radius $\pi$ in every tangent space. The cut locus remains smooth and convex under small perturbations of the metric, since it's far away from the conjugate locus. But there are also modifications of the metric that make the curvature negative in places without changing the geodesic flow very much.
A positively curved metric tends to focus a family of geodesics, making the wave fronts (curves perpendicular to the geodesics) bend toward the concave sense so that the total geodesic curvature of the wave front decreases (by an amount equal to the total Gaussian curvature they sweep through). Negative curvature bends in the opposite way. But just as camera lenses are often designed with both convex and concave elements, you can put some negative curvature into the mix and still make geodesics focus. The cut locus is determined by the shapes of wavefronts at the time they collide, and wherever he net geodesic curvature of any segment is less at the time of collision than the corresponding angle in the tangent space, the precut locus will be locally convex. (But note that to get the full local convexity description depends on geodesics from both sides).
On $S^2$, another phenomenon takes place: the cut locus for the round metric is also the conjugate locus, where geodesics actually focus. In small perturbation of the metric, the cut locus typically becomes a planar tree, which can have arbitrary combinatorial complexity, and can even have infinitely many branches. This is closely connected to the possible cut loci for smooth curves in the plane, that is, the set of centers of disks with interiors inside the curve and boundary circles that touch the curve in two or more points.
Added: here is a picture of a cut locus that can occur for a perturbed metric, in a small area near the antipodal point on $S^2$. The computation is actually the Voronoi diagram for 200 points around the image of the unit circle under $z \to .03 z^5 + .01 z^2$. The wave front shown has started to look significantly irregular, but at a radius 100 or even 10 times as large, it would look very nearly round. Cusps are formed at the focal points at tips of trees, and along the edges, wave fronts arrive from two directions at a definite angle.
The same trick can work to get metrics with convex precut locus on $S^2$ even though they have patches of negative curvature: a very localized $C^3$-bounded change of the metric can make curvature have localized areas of negativity, but it changes the exponential map near the cut locus by a $C^3$ small amounts. The precut locus will be perturbed by only small $C^2$ amount and remain convex.
Added For the case in the figure above, we can see the conjugate locus by drawing rays perpendicular to the curve, showing the geodesics; the fold lines in the picture give the conjugate locus. Each tip of the cut locus is a cusp of the conjugate locus; waves coming from one side of the point focus behind the cut locus. In this case, the conjugate locus is visible as an 8-pointed star with 4 long points and 4 short points ending at the ends of the cut locus tree. This figure shows 1400 very thin lines, and shows a larger region than above.
Additional: how to visualize the Jacobi equation. The behavior of geodesics is described by the Jacobi equation, which says that the second derivative of signed distance from a geodesic to infinitesimally nearby geodesics equals -(Gaussian curvature) times distance. Integrating this equation amounts to taking the limit of composition of sequence of elements of $SL(2,\mathbb R)$, acting on (distance, derivative of distance).
This can be visualized by looking at the action of $SL(2,\mathbb R)$ on the hyperbolic plane, which we can coordinatize as the upper half plane $im(z) > 0$. The boundary of the upper half-plane corresponds to the set of slopes of lines in the plane, with 0 corresponding to parallel variations of a geodesic and infinity corresponding to variations of a geodesic that keep distance 0 and turn at an angle. In general, each points on the circle at infinity tell us the curvature of an advancing wave-front. If the point is on the right, the wave front is convex; on the left, concave.
If curvature is 0, the point at infinity is fixed, and the action is a unit speed translation to the right in Euclidean terms, a parabolic transformation in hypebolic terms. Curvature creates an additional effect that moves the point at infinity: positive curvature moves it counterclockwise by adding a parabolic vector field fixing 0, and negative curvature moves it clockwise.
The instantaneous sum of these two motions is rotation around a point in the positive curvature case, and translation along a geodesic in the negative curvature case. Thus for positive curvature, the wave front shapes make complete circuits around the circle at infinity, alternating between local convexity and local concavity. In the negative curvature case, once convex they always remain convex.
I don't want to make this answer even overlier long, but it should be clear from this concrete picture of the Jacobi equation that we can put in smooth little blips of negative curvature without changing the qualitative nature of the wave fronts at the time of the collision that forms the cut locus, and thus not destroying convexity of the precut locus.
True but not relevant to the question:
Given $x\in M$, the domain of injectivity (of $\exp_x$) I am speaking about is the set of velocities $v\in T_xM$ such that the geodesic starting at $x$ with initial velocity $tv$ is minimizing between $x$ and $\exp_x(tv)$ for some $t>1$ sufficiently small. This set is a an open bounded (star-shaped w.r.t. $0$) set with Lipschitz boundary in $T_xM$. The image of its boundary by $\exp_x$ is the cut locus (from $x$).
I agree that if you perform a $C^3$ perturbation of the round metric on $RP^n$, then the (uniform) convexity of injectivity domains is preserved. But if you perform a modification on the metric (on $RP^2$) to make it negatively curved near some point, you need to do a large perturbation in $C^2$ topology (on the metric). Thus, your geodesic flow will be deformed (much) in $C^1$ topology. You claim that the convexity properties is preserved ?
Concerning spheres, it can be shown that under small perturbations of the round metric in $C^4$ topology, the (uniform) convexity is preserved.


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First Lady and the younger generation
FLOTUS didn't just say "let's move." She interacted with children in her "Let's Move" campaign and moved, too. From exercising to gardening to dancing, check out how the First Lady interacted with kids all over the world.
This photo gallery is featured in these articles:


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The 7 Most Bizarre Objects to Ever Fall from the Sky
You've probably heard the urban legend about the time it rained frogs somewhere, or seen news stories about a meteorite that crashed through a roof and landed feet away from somebody's recliner. But in the annals of baffling objects that have come raining down from the heavens, you find much weirder examples ...
#7. Lots and Lots of Worms
In 2007, Eleanor Beal was making her way to work at the Jennings Police Department when she sensed that something was amiss. Spidey senses tingling, Beal then observed what appeared to be small brown balls raining down from the sky.
Now, this is one of those situations where there is zero chance that closer inspection is going to make you feel better about what is happening. What's the best case scenario for squishy brown blobs from the sky? An explosion at a nearby fudge factory? Well, Beal took a closer look anyway and found that the objects were actually large, crawling clumps of tangled-up worms. To make sure that she hadn't completely lost it, Beal called a co-worker, who confirmed that there were indeed globs of worms littering the parking lot.
Via Miraclegreat.com
"Ah, so we're entering the last days, then. Pardon me; I have to go fuck something."
So where did they come from? Since they probably didn't spontaneously generate in midair, scientists' best guess is that a water spout sucked the worms out of nearby Lacassine Bayou and then -- apparently -- attempted to turn them over to the police. The obvious problem with this theory is that it fails to explain how or why so many worms were hanging out in tangled knots just waiting to be airlifted to the station.
The best part of this creepy crawly mess? It's happened before.
In April 2011, physical education teacher David Crichton was playing soccer with his students at Scotland's Galashiels Academy when another mysterious wormfall began. Crichton said he heard a "wee thudding noise" as the worms impacted the ground, followed by the shrieks of students as they headed for cover.
Via Kingdom News Agency
"Right, oo's up for a pint!?"
Crichton and other teachers found worms scattered over a hundred-yard area, including the artificial grass soccer and tennis courts. Crichton checked with instructors from the school's science department, whose extremely technical expert analysis was that "maybe it was a freak weather thing." Lacking any better suggestions, we'll go with that -- never mind the fact that the day was completely cloudless and water-spout-free, and that Galashiels is about 40 miles from the nearest beach.
#6. A Cow
In November 2007, Charles and Linda Everson were traveling down Manson Highway in Washington State, where they were celebrating their very first wedding anniversary. As they drove along, probably holding hands and whispering the sort of sweet nothings that make single people vomit, a 600-pound cow dropped out of the clear blue sky and onto the hood of their minivan.
After they finished shitting themselves and gazing in abject horror at their new hood ornament, the fortunate couple realized they were, against all odds, uninjured. Authorities arrived, euthanized the cow, and reminded the already traumatized duo that they'd missed a gruesome and untimely death by "a matter of inches." Because, you know, that was just the sort of thing they were likely to forget quickly.
"This is completely unsatisfying. Would you mind standing back and throwing the steak at my face?"
As for the cow, it probably plummeted to its (eventual) death from the top of a 200-foot cliff near the highway. In what we suppose was a fit of adolescent bovine angst, the year-old cow had run away from its Chelan County farm two days prior to the accident, slowly making the 5-mile trip to the precipice where it then went BASE jumping sans parachute. Because cows are stupid.
#5. A Live Shark
We wish we could tell you that one day a golfer was lining up his putt when a goddamn falling shark bounced off his head. But unfortunately, it appears that no one was around when, in October 2012, a live leopard shark fell out of the sky and onto the 12th tee at the San Juan Hills Golf Club in San Juan Capistrano, California.
An unsuspecting course marshal (the guy who yells at golfers when they play too slowly) happened upon the 2-foot-long animal while on patrol. Oh, did we mention that it was still alive? So, in what was probably the high point of this dude's career, he loaded the flopping thing onto his golf cart and got to pull up to the clubhouse with a freaking shark in his back seat.
Via Golfmagic.com
"Dude ... let's find another one, tape them to the ends of sticks, and make shark swords!"
Since it stubbornly refused to die, someone had the wherewithal to put the poor thing in some actual water, where it "wiggled around" while being ogled by most of the staff. Finally, an employee made the 5-mile drive to the Pacific Ocean, where he released the shark and it swam away, effectively giving fate the middle finger. Again. That's right -- it lived. At least, it lived long enough to re-enter the food chain, where it will likely realize its destiny by being eaten by another, larger shark.
So how did it end up on a golf course? It was probably snatched from the ocean by a bird, since employees noticed puncture wounds and a small amount of blood near its dorsal fin. This dude managed to endure the bad-day-for-a-shark trifecta of being picked up by a bird, faceplanting in the middle of a golf course without dying, and spending countless minutes being poked and prodded by caddies while slowly asphyxiating. According to experts at the Ocean Institute in Dana Point, the only birds native to the area with the necessary strength to hoist a shark and fly 5 miles with it are ospreys and peregrine falcons, and if the shark had been any smaller, odds are excellent that he'd have finished his day being reconstituted as bird poop.
Phil Lanoue via Carolinabirdclub.org
#4. Raw Meat
In October 2012, a teenager taking a horseback riding lesson got hit in the head by a hunk of falling chicken. Cassie Bernard of Assawoman, Virginia (yes, that's really the town's name), was in the middle of her class when the raw meat impacted her riding helmet, which conveniently doubled as a meat shield. Two additional pieces, both larger than the one that hit Bernard, fell to the ground nearby. The instructor, parents, and students who witnessed the meatfall said that the sky was clear and offered no clues as to the origin of the meat.
The first suspect was a nearby food processing plant, but the management predictably and vehemently denied that the chicken parts were theirs. Another likely candidate was a local farm, which may have failed to properly dispose of their dead chickens. Scientists did manage to agree on one point, saying that no matter where the meat had come from, high-flying seagulls were probably responsible for the bombing run. Apparently, gulls are complete assholes and do this sort of thing from time to time.
"Fuck you."
For instance, way back in March of 1876, The New York Times ran a story about a Kentucky housewife who was making soap in her yard when it literally began raining meat. Raw and apparently fresh, the meat "fell like large snowflakes" with a few larger pieces mixed in. The meatfall continued for several minutes, eventually blanketing the woman's entire yard. At that point, she decided that she really had to call someone to come check this shit out.
Several men stopped by to observe the carnage, and all bore witness that the meat was indeed stuck to the fence and scattered all over the ground. The two gentlemen who tasted some of it said that it was probably either mutton or venison.
Yeah, that's right. They ate it.
A scientist gathered and tested several samples of the meat, and while he confirmed that it was "of animal origin," he could offer no real explanation for how or why pulverized bits of it had dropped out of the sky. However, he did suggest the possibility that vultures flying overhead could have barfed up bits of their last meal, which they vomited down on the unsuspecting housewife.
And then her neighbors ate it.
"Oh, man, I cannot wait for those things to puke! Honey, get out the frying pan."


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What we learned: Week 5 edition
As the halfway of the 2012 season approaches, we have some huge matchups games in Week 6. On Friday, in the Naugatuck Valley League Brass Division, it's Derby versus Wolcott; in the Copper Division, it's Holy Cross versus Naugatuck.
Then comes Saturday night in the Central Connecticut Conference, it's matchup of divisional leaders and two undefeated teams: Glastonbury versus Southington at Falcon Field in Meriden.
Looking back to Week 5, we saw the much anticipated return of David Coggins at Sacred Heart, the continuation domination of Naugatuck's offense and undefeated seasons of the two remaining NVL teams — Ansonia and Wolcott — continue.
Here's five others things we learned:
1. Sacred Heart first-year coach Cortez Johnson called David Coggins "a special player." After a month of idle time on the sidelines, Coggins made his impact known right from the outset against Crosby by chasing down Roshawn Gainey on the opening kickoff to save a touchdown. There's no ill-effects to his right ankle surgery from August, 2011. His 64-yard strike from Javon Martin was a thing of beauty, as was his 80-yard TD kickoff return and his 22-yard TD off a swing pass. May a great start lead to a fantastic finish.
2. Wolcott quarterback Mike Nicol has some broad shoulders. The senior has carried the Eagles on his back for the past 17 games that he's been the starter. His six-TD performance against Wilby and his previous week effort against Seymour has shown his grit. Expect much of the same for his final five games of the regular season.
3. Sophomore Saiheed Sanders became the Ansonia Chargers' emergency starter at tailback for junior sensation Arkeel Newsome and rushed for three touchdowns and over a 100 yards. It's nice to know that coach Tom Brockett can get a fill-win player to make an immediate impact. Having another option at midseason is a nice problem for Brockett and the Chargers and a huge problem for their remaining opponents.
4. Naugatuck has scored 179 points in the last four games, including 54 points in their latest win against Torrington. While the offense, led by Mick Pernell, takes center stage, my belief is that the defense could be the key for the remainder of the year as they hope to keep pace for the Copper Division title. Shawn Kuczenski's defense is going under the radar, but their importance can't be overlooked.
5. As a freshman, Holy Cross' Isaiah Wright became a dominant, impact player on both sides of the ball. He intercepted passes, caught TD passes and made the Crusaders better. He regressed a little bit through the first four games as a sophomore. Then came last Thursday when returned a punt 95 yards for a score. Wright's physical ability, along with speed and instincts are unparalleled. He just needs some consistency and perhaps a little more focus. If he gets those two intangibles, look out.
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Let's go through these issues, their causes and their implications.
Cause no. 1: The supply problem
Supply conditions for goods and services continue to deteriorate in
Since 2001, French industry sales prices have been falling relative to unit wage costs. Such falls reflect the excessive level of unit wage costs compared to the sophistication of industrial production in
However, the rise in the unit wage cost – relative to selling prices – does not come as a result of the trend in productivity, but what has been happening to wages. This is because the level of costs is pushed up by the level of employers' welfare contributions.
The subsequent fall in French industry's profitability is substantial, reducing its capacity to invest and create jobs. This leads to the off-shoring of production capacity to countries where industrial profitability is higher, thereby weakening industry financially and threatening it with a serious crisis in the event of a recession and falling demand.
Cause no. 2: The demand problem
Between 2011 and 2012, French industry suffered from the weakness of both domestic and external demand. This resulted in a lower capacity utilisation rate than normal, which makes the problem of low profitability even more detrimental. And the decline in demand may deteriorate further if there is a fall in real wage incomes and government expenditure.
Cause no. 3: The euro-zone crisis
The eurozone crisis has two negative effects on French industry:
- it weakens demand and therefore imports in the eurozone countries that usually would have been
France's customers. This is significant because the eurozone accounts for 46% of French exports – the United Kingdom, which is also mired in a recession, accounts for 6%;
- it reduces domestic demand and capacity utilisation rates in
Spainand Portugaland persuades industrial companies in these countries to turn to exports. As wage costs are lower in these countries, there is an increase in the competition that has a direct impact on French industry. France's export market share tends to decline, whereas those of Portugal, Spainand Irelandhave recovered.
Remedies are very difficult to implement
Of the three issues mentioned, weakness of demand and the effects of the eurozone crisis cannot be controlled, particularly in a situation where there is private-sector deleveraging and a reduction in fiscal deficits. The question for French industry is therefore which remedies can be implemented on the supply side? We have put together the following list of possible measures:
- an improvement in the sophistication of industrial production and in the differentiation of products, which will require innovation, investments, and marketing;
- increased geographical diversification in companies' sales to increase the weight of emerging countries, which is currently quite low in
- a major reform of the financing of social welfare in
Franceto reduce the weight of welfare contributions paid by companies;
- a fall in the hourly labour cost, either through a fall in the per capita wage, or through an increase in the number of hours worked (which is obviously a source of conflict).
However, these measures are all very difficult to implement rapidly.
It is also important to understand the major fragility of companies that are not very profitable (i.e. they have a shortfall in supply) when they are faced with a significant and lasting decline in demand.
Unfortunately, it looks as though this French industry crisis is not going to go away any time soon.


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In Galatians 2:18, Paul writes, "If I rebuild what I destroyed, I prove that I am a lawbreaker." What is he referring to when he mentions rebuilding what was destroyed and how does that answer the objection that is raised in verse 17?
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To understand what Paul is saying here in Galatians 2:17-18 it is helpful to read the context starting from Galatians 2:3-14.
However, to cut to the chase - Paul "destroyed" or "tore down" the idea that a person can be justified by the Abrahamic/Mosaic laws of circumcision/diet.
When Paul states, "...I prove that I am a lawbreaker.", he is saying that if he were to "put back into place" the idea that one can be saved through the works of the law (as Peter was hypocritically suggesting in Gal 2:11-14), then he (Paul) would be amiss.
I don't make a habit out of reading the New Living Translation, but its paraphrase on Gal 2:17-18 may be more helpful to you than the thoughts that I've shared already.
According to early church interpretation it's the law or the works of the law.1
1: Tertullian, adv. Marc., 5,3,8; Eusebius of Emesa, in Gal.; Ephrem, in Gal.; Augustinus, Exp. Gal. 16,7-10; Ambrosiaster; Theodoret of Cyrus


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With the registration period just around the corner, you're probably starting to think about the classes you'd like to take. Scheduling is not as simple as it looks. You need to consider classes are mandatory for graduation — required courses, your ALWR, foundation points, mandatory credits, and also keep in mind CPE credits. You can find all of these requirements on the FCSL website. Review the Registrar's web page as well as the Student Handbook regularly. Being well informed will ensure you are selecting the classes to graduate on time.
Further, you need to develop a plan for the classes you want to take before graduation so that you don't miss out on any opportunies to take courses that are taught infrequently. Think about the area you plan to practice in — if you plan on working in the criminal field, do you want to take Trial Practice? Consider what state's bar exam you will take and what subjects are tested — can you take classes on those topics to get an early start on bar prep? Even if the material is not exactly the same, you may get a foundation or gain an understanding of the terminology used in the subject.
Consider asking other students about classes and professors they enjoyed or recommend. Make sure you look at the schedule for final exams to ensure you are not taking back-to-back exams. Have a healthy mix of classes — consider taking skills courses along with doctrinal classes. Do not wait to take your ALWR course in your final semester. Make sure you get a degree audit each semester from the Registrar and continue to regularly check to see if you are on track to graduate.
If you're still confused about registration, or would just like some advice about what courses might best suit your needs, schedule an appointment to meet with one of the Academic Success Counselors. Pay attention to the requirements for a scheduling meeting that were included in the e-mail sent out from our department this week. We look forward to helping you select the schedule that's best for you!


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TOPEKA -- Nearly a year after the negotiated departure of Norton Bonaparte, the Topeka City Council will take a giant step Saturday to placing someone permanently at the helm as City Manager.
An impressive list of community leaders joined a few other local voters who wanted to meet Jim Colson and Margie Rose. They're the two finalists chosen by the Bob Murray and Associates search firm to interview today for the city manager's position.
Colson, the assistant city manager in the Phoenix suburb of Glendale, Arizona said they were both driven around the capital city Friday and were impressed with what they saw. In the session at the Holliday Building, Colson said "people are focused on the future of this city."
Margie Rose brings more than 25 years experience with previous duty as a city manager in Inkster, Michigan, and currently serves as the assistant city manager of Corpus Christi, Texas. What were most people telling her?
"Lots of Topekans are concerned about their neighborhoods, asked what I knew about neighborhoods and how I could help them. I have that experience and know that it requires engagement of the city and its staffers, and engagement of the neighborhoods."
"After meeting here tonight, I am more invested and excited about the opportunity to be part of the Topeka family."
Colson also said he would give serious consideration to the city manager's position if it's offered to him, "or else I wouldn't be here."
Speaking of his arrival for his previous job, Colson said, " Glendale was a city with lots of good resources, but hadn't had much economic development success. Working with the city and other groups we became a success in economic development, hosted a Super Bowl, and are getting another one."
Colson said he'd be interviewed in the early afternoon, but no official timetable was released by the City of Topeka on the schedule for council members to talk with pair of candidates today.


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If I am teaching myself a foreign language as a leisure activity, may I write in a workbook on chol hamoed, for the purpose of retaining my knowledge? If I haven't begun, may I start the new language if it involves writing?
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The halacha is much more lenient about computer use. R' Dovid Zucker and R' Moshe Francis permit it completely in their ArtScroll sefer on the subject (though they mention potential issues with printing). Unless you're trying to learn to write a new alphabet (e.g. Chinese), you could avoid questions by doing the worksheets on the computer.
Hebrew may have room for leniency as well if you are doing limudei kodesh. The halacha allows one to write chiddushei torah. So I asked before Chol HaMoed about writing translations of difficult words in a sefer I was learning, and was told that's OK. CYLOR.
According to Rama in Siman 545 - We are Maikel with writing on Chol HaMoed as it is not a Maasei Uman. However as YDK pointed out the Pri Megadim says explicitly that this Halacha does not apply to a Yachid. See also more notes on bottom.


text: Sports Pictures: 25 Olympic sports we want to see With the 2012 London Olympics around the corner, here are 25 sports that should really be included. Really. This photo gallery is featured in these articles: The Morning Call Established storytelling, new-media outlets for Olympics on NBC The Morning Call Get that London look in Baltimore


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Aiya News
New Radiation Test Results for Our January Shipment
We received the new radiation test report for our Matcha shipment for the month of January. The test shows that our Matcha is still safe for human consumption based on the regulations of the FDA and Japanese Government.
If you would like to see the test results please contact us and we can forward you the test results so that you can view it for yourself. The test is performed by a 3rd party lab located in Northbrook, IL.


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A BCS Mismatch? Don't Blame Northern Illinois
Northern Illinois, the poster child for Bowl Championship Series mismatches this college-football postseason, may be getting a bum rap. It had to finish ahead of at least one major-conference champ in the BCS rankings. As it happened, the football gods handed the Huskies two: Louisville (Big East) and Wisconsin (Big Ten).
No. 21 Louisville takes on No. 3 Florida in the Sugar Bowl and unranked Wisconsin faces No. 6 Stanford in the Rose Bowl. While Wisconsin looked formidable in beating Nebraska by 39 for the Big Ten championship, the Badgers looked less so in losing to four unranked opponents this season on the way to a pedestrian 8-5 record. And the Badgers' loophole for entry into the BCS was bigger than Northern Illinois's: They got into the Big Ten title game only because Ohio State and Penn State (two teams ahead of the Badgers in the Big Ten's Leaders Division) were ineligible for postseason play. Meanwhile, No. 15 Northern Illinois is only ranked three spots behind No. 12 Florida State, its Orange Bowl opponent.
Overall, the historical record isn't promising for Wisconsin and Louisville. During the history of the BCS, which began following the 1998 regular season, six bowl games pitted ranked teams against an opponent ranked 10 spots or more lower. Those six underdogs all lost.
Stanford and Wisconsin actually met in one of the mismatches—with the favored Badgers winning 17-9 in the 2000 Rose Bowl.
—Carl Bialik