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

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 ...

Time was when a valve job was done with some valve-grinding compound and a vacuum cup on a stick. But no more. Today's high performance engines require the same machining precision in the valves that ...