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

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

One of the most common valvetrain upgrades for pushrod-style engines is roller rocker arms, which are often said to increase horsepower through reducing friction. But is it true? You’ll find out on ...

It's no big revelation that high-lift rocker arms (those with a greater multiplication ratio than stock rocker arms) generally increase the performance of an engine without necessitating a camshaft ...

The rocker arm is possibly the third most abused part in your engine. The connecting rods take the cake for the most abuse, followed closely by the piston assembly, but we like to think the rocker ...