Obviously, these valve-control-related issues, associated with insufficient valvespring pressure, are the reason why camshaft manufacturers offer valvespring upgrades. The obvious answer might seem to ...

For mild street engines, stock valve springs are more than adequate. But if you've screwed in a big bumpstick for strip-banging or banzai runnin', then pay attention. Our plan was simple: Install a ...

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 ...

Before starting this valvespring story I thought I had a grasp of its mechanics, but then as it developed it became ever more complicated until it reached a point where I doubted if I had any ...

A small gap with big importance in the performance and health of an engine - here's everything you need to know.