Re: Comp Cams

[Todd Tomason <jayscore@xxxxxxxxxxxxx>]

Here's the info that Jock had from Tim Cole at Comp Cams:

Hi Jock, 
Flat tappet cams in general have some common thread problems.....the
problems are not just with COMP Cams. ?Someone missed the info just a
little....the problem with the EPA has nothing to do with the way the
cams are made...it has to do with the oils that are available to the
public now. ?The government has 
forced the oil companies to delete some elements from the oils under the
guise of protectiong the environment. ?The most crucial of those deleted
elements is ZINC! ?The property of zinc in oil is that of adding
lubricity between metal surfaces....especially during the critical
break-in process of a flat tappet cam. ?The loads between the lifter and
the cam are incredible! ?Now that zinc is gone, the cams are much more
vulnerable to flattening during the break-in/burnishing period. ?That
being said, there are also a number of other things that customers
sometimes ?do that are not in their best interests.....the lifter MUST
spin at all times. ?If there is only .002" or so clearance between the
lifter and the block, the smallest piece of grit that does not get
cleaned from the motor, or a piece that breaks loose from some nook or
cranny, can lodge between the lifter and block and...WHAM....the cam goes
flat in seconds.....lifter doesn't spin! ?When a new cam is put in and
the valvetrain is assembled, turning the motor over by hand with the
manifold off will show if the lifters are turning (caused by the taper in
the cam against the convex surface of the lifter and their contact point
off-center on the lifter). ?We've already talked about the loads and the
oils during burnishing....there are additives, like our Camshaft Break-in
Lube (12 oz. bottle part number 159, approx cost $10) that can be mixed
with the break-in oil to replace some of the lost lubricity. ?There is a
lifter bore grooving tool that's used by most of the oval track engine
builders in the country, and a significant number of street engine
builders, that "scribes" a .012" or so groove in lthe lifter bore on the
side of the bore leading the cam lobe so that a constant, very small,
stream of oil is constantly lubing each cam lobe just prior to them going
under their respective lifters. ?Remember, the reason we break these
motors in at 1,800 to 2,000 RPM for 20 minutes or so is so that the oil
is splashed up onto the surfaces of the cam and lifter to get oil between
the two. ?As soon as the motor comes back to idle, THERE IS NO MORE OIL
PROVIDED TO THE CONTACT SURFACES!!!!....at least not until the motor is
revved up again. 
Other things that can happen to create flattening are as simple as the
bottom of the retainer touching the top of the valve guide....cam goes
flat......too much nose spring pressure during break-in or coil bind
caused by lack of checking actual lift versus the available room between
the coils....cam goes flat. 
OK....this is a real long explanation of the short question..."why did my
cam go flat?", but as you can see, the answer is not simple....but the
thing I want you, Jock, and others you encounter to know as gospel is
that we do not produce "soft" cams alluded to below, and the EPA has not
required us or anyone else to do such a thing. ?Just a case of
misinformation and internet chat spreading incorrect information. ?Hope
this helps clarify! 
Thanks for getting in touch with me! ?Look forward to seeing you again
soon...and happy racing to the AMC folks this year! 
Tim Cole 

COMP Cams Performance Account Manager