Crower Valve Train Components

This booklet is a general installation reference guide for Crower valve train components. The information is intended to give you a good basic idea of what building a reliable and powerful performance valve train requires. We’ve tried to eliminate the “surprises” and provide you with solutions to any snags you might encounter. It should help minimize your anxiety when there’s more to a job than you planned on, or when parts don’t fit properly.
Most of the information is based on common sense. However, in presenting the following tips, do’s and do nots, we have assumed you have a certain amount of automotive skill and knowledge. If you don’t ask someone who does and read all you can on performance valve train systems for your engine to familiarize yourself with the subject.
Proper installation of Crower valve train components will require precise measuring, and in some cases precision machining. If you don’t feel confident enough to do it yourself, by all means have a competent engine builder do it for you. You may find it well worth the nominal money spent to have the job performed correctly.
THIRTY MINUTES after an engine with a new camshaft is started for the first time, the initial stages of cam lobe failure may have begun! And no corrective action will prevent the process from continuing until one or more lobes are damaged so extensively that the engine will not operate properly. This doesn’t mean that camshafts are delicate. But camshafts, like any other precision parts, must be treated with respect. A camshaft in a V-8 engine turning 6000 revolutions per minute is subjected to 800 high load impulses every second. Modern camshaft and lifter design, plus efficient lubrication systems, enable the camshaft to stand up under this load. But if the camshaft lobe-to-lifter-face relationship is altered, or lubrication is inadequate, camshaft failure is probable.
WHERE LOBE MEETS LIFTER
The camshaft lobe-to-lifter-face relationship is an interesting subject. From all appearances, the cam lobes are straight across, but actually, on all except a very a very few engines, cam lobes are tapered. The lobe taper may be from .0007” to .002” across the face. The lifter faces are also shaped differently that they appear. They are ground spherically with a .002” crown in the center. When the camshaft is in place and the lifters installed, the lifters are offset slightly from the cam lobes.

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