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[Jim Davies]

On Mon, 23 Feb 1998, Christopher E. Hill wrote:

> 	I am sorry if I have caused any confusion.  Yes, the pressure due to
> combustion does produce a stress on the conecting rods.  However, the
> stress due to rpm on the rod I feel is higher than that of combustion.  I
> have not done the actual math to prove this, just using my common sense, as
> I have never seen a rod broken under normal cicumstances(i.e. lacking
> SEVERE detonation) but have seen some come appart at high rpms.  

The last SAE paper I saw on this subject showed the load at TDC exhaust to
be far higher than any other load on the rod, including the power stroke.
I have read of Allison rods breaking from detonation related problems,
which could become severe enough to push crankshafts out of the block, but
these were highly loaded, very highly supercharged engines using 150PN
gasoline. We are not going to see similar cylinder pressures with the
fuels currently available.

Jim Davies