General Motors has filed a new patent that offers a look at how the company may be rethinking cylinder deactivation for its ...

A recently filed patent details a new GM cylinder deactivation system that appears to be heading to the next-gen V8 engines ...

GM has filed a patent application a variable displacement valvetrain system with rocker shaft porting and insert sleeves for ...

The rocker arm employs the use of a fulcrum or pivot to increase the cam lift by a given ratio. That increase in lift is the result of moving the pushrod pivot point closer to the fulcrum. That ...

Overhead cams are a more efficient method of actuating the valves than with a pushrod, but someone in Detroit never got the memo. And thank goodness they didn't. With production pushrod mills turning ...