Good machine shop work is hard to find. Shop around for price on the align
bore and cam bearing
job, but get some references that you can check on as to the quality of the
work. You don't, I am
sure want to end up with a ruined block. As to shot peening, I certainly don't
recommend doing that to any standard English con rods. When we were racing a
Lotus Super 7 in the early 70's, the only rods that ever came up not passing
magnaflux inspection were shot peened . On two occasions when a crank broke
and bent two rods each time into pretzels, the rods still passed a mag
inspection after the blow up. These rods had not been shot peened. I would
much rather have a rod bend than have it break. My theory ( and I am certainly
open to better information) is that standard English rods are in an "as forged"
condition, which is pretty soft. Shot penning work hardens the surface of the
rod. Under
high rpm inertia loads the rod wants to stretch, the inside metal is not hard
enough to resist the load and stretches. The outside that has been shot peened
is very hard and will not stretch, so it cracks. If the rods were heat treated
to the proper overall hardness before the shot peening, then they would
probably come out strong and tough as we would like them to be. I like to
smooth all of the irregularities from the surfaces of the rods and then GLASS
PEEN them. If done with the
proper size beads and with the correct air pressure, this gives a proper
uniform surface finish with
no stress risers and should stress relieve the surface with out the detrimental
work hardening.
-----Original Message-----
From: DAN DURYEE [SMTP:DLDEAD@worldnet.att.net]
Sent: Friday, November 13, 1998 9:51 PM
To: Bob Lang; triumphs@autox.team.net
Cc: fot@autox.team.net
Subject: Re: Align Boring for Cam Bearings
Hi Bob, I had a cam seize in the block several yrs. ago. in the GT-6. I
got
cam bearing from Ken (BFE) and had them installed here in Denver, cost
was around $250. Most any good engine builder should have a shot -peener.
Dan
SDS Racing
----------
> From: Bob Lang <LANG@ISIS.MIT.EDU>
> To: triumphs@autox.team.net
> Cc: fot@autox.team.net
> Subject: Align Boring for Cam Bearings
> Date: Friday, November 13, 1998 10:02 AM
>
> Hi All,
>
> I'm performing a sanity check:
>
> TR engine block - align boring for cam bearings...
>
> I got a price of $375 for the job.
>
> It sounds high... can anybody provide numbers that support this price???
>
> Oh, and I'm looking for someone to shot-peen some TR6 rods. Any pointers?
>
> C ya,
> rml
>
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