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2
Here is a close-up look at the lobes on a Crane blueprint camshaft
for a 427/425 HP big block Chevy (part number CRN-1969961). Most
flat tappet camshafts have a similar lobe shape.
3
5
Here’s a disassembled Crane
solid flat tappet lifter. The inner
workings are simple.
This is a fully machined tool steel lifter from
COMP Cams, designed for use in severe duty
NASCAR applications where RPM levels and
valve spring loads are high. The body has
a Diamond-Like Carbon (DLC) coating that
hardens the metal surface to be extremely
slick and wear resistant. The lifter internals
are actually one piece instead of two as
normally found on conventional lifters. Lifters
like this are at the super high end of the
spectrum, and they aren’t cheap.
This is a closeup of a COMP Cams Stock Eliminator camshaft lobe.
The lobe shape is more “square” than the lobes on the Crane cam
in the previous photo. This allows more radical valve opening and
closing rates.
4
See the tiny hole in the base
of this COMP Cams solid lifter?
It’s been Electrical Discharge
Machined (EDM) into lifter base,
and is designed to add more
lubrication between the cam
lobe and lifter face to improve
reliability. There are two EDM
arrangements available—one
centered in the lifter base and one
drilled offset. As the lifter spins,
the offset hole will lose contact
with the cam lobe, but some engine builders have a preference
for this design.