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 ...

Performance is all about pushing the envelope. As camshafts become more aggressive in the search for more power, these lobes make life increasingly difficult for valvesprings. This may seem like a ...

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 ...

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 ...