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Discussion Starter #1
:craz28: So My engine vibrates like crazy. I have established that it is rpm related and matches the engine speed in neutral. The problem can be significantly magnified when downshifting. In neutral it blurs my mirrors and makes things shake that are securely in place.

First attempt to fix I removed the belt to rule out accessories. Still there.
Then I removed the brand new clutch and pressure plate Still there.
Messed with the balancer on the front even though it is supposed to be neutral balanced removing from the crank and rotating didn't help.
The rubber on the pulley is a little dryrotted but I don't think it has slipped.
regardless it vibrated with it off too. And it doesn't wobble excessively.

So Now I am at the point of no return. I think the best move is to get a flywheel because the one I have I had a shop attempt to balance it per the factory specs (this is after the first diagnosis as the flywheel) and I think they nuetrally balanced it. Even though I specifically asked about it and explained the lt1 being externally balanced and that i had a vibration problem
They said no big deal balanced it with the pressure plate installed.
I think it's nuetral because there are many drill marks on the back and all the factory ones I have seen have very few and certainly no drill marks on the weight itself. I will take a picture of the back of it later but it has at least 12 holes drilled in it in three different spots plus factory weights on the outside

I ripped it apart for the third time yesterday and found this. Most likely from vibrating so badly? what do you think?>

Pressure plate and flywheel are screwed all chattermarked and hotspotted on one side. (points to out of balance)?

Something deep down tells me the crank is bent or something catastrophic in the engine balance.

The only thing I can do Is try a new flywheel and if it doesn't go away it has to be in the bottom end right? There isn't anything else that would shake that badly.
Maybe I am being a wuss and lt1 are groundshaking and uncomfortable but my ls2 gto Is 100% smoother in all aspects. Camaro would be undrivable to about 99% of the world. The clutch takes some crazy practice you have to rev it alot so it won't die. It feels like I have solid motor mounts and a cat stuck on one side of the flywheel. Definitely doing a number on my bearings.

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