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 ...

An engine's valvesprings play a critical role in its performance, yet those incorrectly chosen for a given application can cause hobbyists to unknowingly point blame in another direction if an engine ...

Four-stroke engines, which make up 99% of vehicles on the road, rely on a system for managing air intake, compression, combustion, and exhaust within a sealed combustion chamber. Poppet valves are ...