Pontiac Lifter Guide - Lifter Lowdown

HPP: Does lifter weight have any bearing on maximum rpm?
CK: The weight of the lifter and pushrod is of much less consequence. It's the weight of the valves, valvesprings, retainers and locks, and the overall multiplication effect of the rocker arm ratio that tend to limit maximum engine rpm. The heavy valvetrain components and stiff valvesprings cause hydraulic lifters to leak more quickly, which can limit maximum engine speed along with the less aggressive profile of a hydraulic roller grind.

HPP: Do your hydraulic roller lifters have direct-axle oiling?
CK: Our hydraulic roller lifters don't use direct-axle oiling, primarily to prevent the loss of internal oil pressure, which could have a negative effect on the lifter's hydraulic function. Instead, we use a dynamic system we refer to as "focused oiling." Since some oil is left behind during each lift cycle, this residual oil on the camshaft lobe and lifter roller wheel is directed to the lifter's needle bearings through channels machined into its body. Both ends of the needle bearings receive a supply of oil for lubrication and to carry away frictional heat without any loss of oil pressure.

HPP: Is continual preload adjustment of any concern?
CK: We recommend that 1-1/4 turns of preload be used to minimize oil volume in our hydraulic roller lifters. Once proper preload is set, there should be no need for future adjustments unless something drastic happens, such as over-revving, which can compromise other components in the valvetrain.

HPP: What types of hobbyist applications do you see hydraulic roller camshafts used most in?
CK: Retrofit hydraulic roller camshafts and lifters are being used in a broad range of applications, from street machines and musclecars to dedicated drag racers. The benefits associated with roller profiles typically include wide torque and power ranges and, when combined with the low-maintenance design of a hydraulic lifter, they seem to provide superior results when compared to a conventional flat-tappet cam and lifter setup. They're also unaffected by modern oil quality concerns.

HPP: Is there any application for which you'd suggest not using a hydraulic roller cam?
CK: We feel it may be more advantageous to use a solid roller cam and lifters in applications that will encounter engine speeds in excess of 7,000 rpm over long periods of time. As mentioned earlier, a hydraulic roller will certainly reach those figures, but the expense of the premium valvetrain components required may not be reasonable for the usage intended.

HPP: Do you see any advantage in combining solid roller lifters with a hydraulic roller camshaft?
CK: This is something we simply don't suggest. It seems some feel that they're saving money by installing less-expensive solid roller lifters on a hydraulic roller cam, but it could cost them in the long run. The lobe profiles of a hydraulic roller camshaft don't incorporate the clearance ramps necessary for the proper operation of solid lifters, and severe valvetrain damage and shortened reliability are very possible. Just the same, we don't advocate combining hydraulic roller lifters and a solid roller camshaft.

Crane Cams
Dept. HPP
530 Fentress Blvd.
Daytona Beach, FL 32114
(386) 252-1151
www.cranecams.com

Comp Cams
Comp Cams remains on the technology forefront and is often considered an industry leader. The company's Research and Development Engineer and Cam Designer, Billy Godbold, explains the features of its solid roller lifters.

High Performance Pontiac: Does Comp Cams produce its own solid roller lifters for Pontiac engines?
Billy Godbold: Comp Cams designs all its lifters from a clean sheet of paper and our solid roller units are no exception-they're processed from bars of steel.