I have had a lot of experience with loose con rod bolts in the earl;y days
of Triumph engine modification. You were just a very short step from having
that rod out the side of the block. The fretting you see on the surfaces of
the rod are from the cap MOVING around due to the clamping not being high
enough. I went to larger ( in your case Carillo) rod bolts that were very
hard and therefore did not stretch, then increasing the torque to 60 pounds
instead of 45. When I did this I first took a small amount off each side of
the rod surfaces, then drilled out and tapped for the larger bolt, then
tightened to the new torque value, then had the rod bored to the stock
diameter to make it round again. When after this everything stayed togeather
and never had another loose bolt or block ruined becuase of rod cap comming
loose. On the break-in of the new engine my suggestion and the method I
follwed is as follows: Bring up the oil pressure by removing the distributor
and bringing up the oil pressure by spinning the oil pump with a speed
handle until the oil was fully circulated, replace the distributor, set the
timing staticly, then fire up and hold the idle steady to 1500 RPM DO NOT
BLIP THE THROTTLE DURING THE TIME. Keep this idle speed for about three
minutes, reduce the speed to normal idle for a couple minutes. Shut off
check for leaks etc, fire up and do the same thing again, DO NOT BLIP THE
THROTTLE. after a couple minutes more of high idle you ready for a drive. I
figured about ten minutes of driving was either going to seat the rings or
scuff them. They always seated. I set the revs to under 4000 durinmg this
period. After that come and get me. The blippingthe throttle on first start
by the way is the quickest way in the world to scrore the camshaft and the
cam followers. But that is only how I did it....."your mileage may differ"
Kas
----- Original Message -----
From: Henry Frye <thefryes@iconn.net>
To: <fot@autox.team.net>
Sent: Tuesday, March 21, 2000 6:48 AM
Subject: A couple questions
> To the dirty fingernail crowd,
>
> Question 1: Upon tearing down the engine in my race car, I found one of
the
> connecting rod bolts was finger tight. My machine shop gave the rod a
clean
> bill of health after magnifluxing, cleaning up the minor spalling on the
> end cap and resizing the big end. It's a stock rod with Carillo bolts. My
> machinist is suggesting a higher than stock torque setting to take
> advantage of the stronger Carillo bolt, he is calling Carillo to verify.
> Does this make sense?
>
> Question 2 is about break in, or should I say the lack of engine break in.
> After getting this engine together, I hope to have the car on the track
> without any real run-in time at all. I'll run it long enough to get the
cam
> and tappets happy, but wasn't planning on disturbing the neighbors much
> more than that. How long should it take to get the rings to bed when
> running at track speed? I am running a very low running time set of
> pistons/rings/liners with a real light hone job to break the glaze. Should
> I use mineral based oil for the entire race weekend, then switch to
synthetic?
>
> I still can't decide what to do with 5 gallons of 3 year old racing fuel I
> drained out of the fuel cell... Somehow I don't think the push mower or
the
> snow plow truck will get the job done any faster with it!
>
>
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