The engines of yesteryear were pretty simple, with tappets clackity-clacking away on cam lobes, opening valves, and making a ruckus while doing it. Mechanical lifters were adequate for valve operation ...

The rules in some racing classes restrict competitors to running hydraulic valve lifters. Cheaters have been known to run hydraulic lifters on a mechanical (solid) cam profile. Solid cam profiles ...

Once upon a time, most car engines used solid or mechanical lifters. But unlike most fairy tales that begin that way, there was no lasting happy ending for them. Hydraulic lifters first appeared in ...

Camshafts are one of the most confusing components in an internal combustion engine. What makes those lumpy bumpsticks even more confounding is the sheer number of grinds available, and then multiply ...