This illustration shows the spring's relationship to the valve. The valve stem goes through the middle of the spring and is positively connected to it by the retainer and two valve locks (also known ...

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 ...