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

A camshaft can be a huge performance component for an engine-many people know this. Cam lobe design is often regarded as a black art. Many who have mastered it prefer it that way to keep people from ...

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

For years, the standard operating procedure for testing new components or ideas has been to eliminate every variable possible, make one small change, and evaluate how that affects performance. It's ...