No flames, here, just some thoughts and this was a good place to attach
them. I agree with Derek. Use the best rod bolt you can buy and install them
correctly for longevity...
Hmmm, I tend to think of the load on rod bolts as pure tensile. Here is
why..when the piston is going down in the power stroke the load is
completely on the saddle of the rod at the big end. When it is on the
exhaust stroke it is pushing the gas out so there is residual load on the
top of the piston, so the rod may or may not be in compression with the load
on the saddle. When it is on the intake stroke the load is on the cap and
the bolts are in tension. When in the compression stroke, it is back to
being a compressive load on the saddle of the rod. The worst loading, in my
opinion, is when we blap the throttle, to ahem, clear the plugs or some
other such. In that case the butterflys in the carb are closed, the pistons
essentially have nothing but inertial loads. And when we rev these puppies
up like that, the the load gets pretty big on the rod caps (pistons want to
keep going on the up stroke).
Sent: Saturday, February 24, 2001 5:09 AM
Subject: Re: Connecting rod torque specs
mayf (b9471136)
> I put in ARP bolts and none of my rods had to be resized (we checked them
> all.) I think the torque was 30lbs with their moly lube or higher without.
> If you ever think of the forces on rod bolts, the mind boggles and the
best
> bolts get bought. cheers, derek
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