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 ...

GM has filed a patent application a variable displacement valvetrain system with rocker shaft porting and insert sleeves for engine cylinder deactivation. The patent application is tagged with patent ...

Over the past couple of racing seasons, the camshaft specialty companies have created dozens of new profile designs, many of which are over the .800-inch-lift mark. Along with camshaft and cylinder ...