Larry,
I can provide some help but not the complete answers. Although over the
years I've never been involved much with racing engines I've seen absolute
garbage supplied as far as decent quality cams and followers go which
weren't fit for stock engines. After seeing lobes disappear from cams from
people like Triumph Tune and Kent we had all reprofiles rehardened and we
didn't have a single subsequent failure. To begin with they were tuftrided
then I discovered a far superior process of ferritic nitro carburise, and
after hardening they could simply be washed and fitted. Items cost around $2
a kilo and previously well used cams didn't bend in the process as they had
no stresses left in them after cycling hot and cold in engines for years.
The best followers are made by the original manufactures whose name escapes
me - they are made from chill cast iron so that the face of the follower is
cooled very quickly when made - it forms very small and very hard crystals.
There shouldn't be any necessity to have them hardened but they can be.
There were problems again with Triumph Tune ones as they insisted on
hardening the cheapest nastiest followers to begin with, and very small
"growth" in them meant a lot of time resizing. Again ferritic nitro
carburise should work.
John Kipping
----- Original Message -----
From: "Larry Young" <cartravel@pobox.com>
To: <fot@autox.team.net>
Sent: Thursday, September 05, 2002 5:13 AM
Subject: Lifter Hardness
> After destroying one valve train, I'm trying to do things right this
> time. I took two sets of new lifters (one from TRF and the light ones
> from Moss) to be hardness tested. All of them tested less than 30 Rc,
> i.e. no hardness. From what I've read in the archives, I should have at
> least 56 Rc for a racing application. Does anyone make decent lifters,
> without going to the smaller GT40 lifters? I'd like to stay with full
> sized lifters. Has anyone considered having lifters made or having the
> soft lifters hardened? Do we know the type of metal they are made
> from? Ok, and now for the stupid question. If the reground cams are
> not hardened, why do you need 56 Rc lifters?
> Larry Young
> Forever Young Racing
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