When I ran stock rods in the Desoto, I ran a six carb set up on a
homemade log manifold with a pressure tank feeding the carbs. We lost
lots of rods. Luckily, with the Desoto, they usually broke close to the
big end and didn't do lots of damage, often I could have it going again
in a couple of hours. But when I retired the Desoto, it had five
cylinder sleeves because of rod breakage and the last on didn't seal out
the water so I finally changed to the Chevy.
In that case we finally found out that that the carbs we bleeding fuel
over into the cylinders causing a hydraulic bending of the rods which
would then break under RPM. On the Chevys I lost several stock rods.
Fatigue and spun bearings were the culprit. With both aluminum and steel
rods it was bearing failure that took them out, not failure of the rods
themselves. In one case, lack of deck clearance got an aluminum rod on
the engine dyno.
You are right John. We shouldn't blame the rods, it is usually other
contributing factors.
Tom
John Beckett wrote:
>
> Just a thought. If aluminum connecting rods work well in Top Fuel and
> other Blown applications why would they be any less acceptable in normally
> aspirated applications? As Tom Bryant says you can break anything. Of all
> the Rod failures that we have collectivly experienced how many were truely
> attributable to the actual fatigue of the rod itself? Or was it something
> else like oiling, or improper clearence, or poor rod bolts, etc.?
>
> John Beckett
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