The KA24E had a single overhead cam and KA24DE had dual overhead cams. They utilize parts which later became known as GT pistons, cams and engine ECU programs. He used truth darts and spy cams. It has the same bore and stroke, but the cams and pistons are unique. He replaced slide valves with valves that used cams. It features VVT for both the intake and exhaust cams. Both versions of the engine contained 4 valves per cylinder and dual overhead cams. The engine was upgraded to dual overhead cams and four valves per cylinder in 1993. The brakes are rod and spring operated with cams inside the drums to actuate. All RB engines have belt driven cams and a cast iron block. The R-Tune was introduced into the NISMO line-up with modifications including headers, cams, pulleys. Compound bows have a mechanical system of pulley cams over which the bowstring is wound. Each valve was independently operated by one of four cams. Multispindle lathes have more than one spindle and automated control (whether via cams or CNC). Another disadvantage is the contact point between the cams and rocker arms.