Those wound-up pieces of high-tensile steel under your rocker arms work so hard closing your valves over millions of cycles that they could probably use a replacement right about now. We're talking ...

You've probably read this line a dozen times: "It's never been easier to make horsepower than right now." While that's true, it also means everything else in the engine is now more highly stressed.

Although the basic purpose of a valvespring is to close the valve while also ensuring that the valvetrain stays in contact with the cam lobe, it must perform this feat under grueling conditions that ...