Butler Performance Inc. - Solid Roller Lifters
Solid Roller Lifters- These lifters have no internal hydraulic mechanism to take up clearance as in the hydraulic versions. They feature a roller in place of the tappet as well. As the cam turns the roller actually rolls along the lobe for less friction. This greatly reduces friction so it can produce more power. This reduction in friction also means no need for additional oil additives. Roller lifters are only to be used with roller cams. The solid roller lifters still require valve lash, or the clearance needed for the lifter to unload when the cam comes around. For valvetrain stability, these lifters require more valve spring pressure to allow them to operate at higher rpm's without valve float. There is more valve noise and maintenance compared to hydraulic roller lifters.