Hmmmm
Well a well....
I wonder why the Rat engine builders use truck blocks with the high deck
allowing use of longer rods? 'Course they run a Bowtie..
All I can say is this: I don't think that Ford had to reuse old parts, and
build pistons with relocated pins in order to save a few bucks. I suspect
that there was a purpose. Reliability, less stress on the skirts and less
friction (and wear) overall, as well as greater time at TDC and better rod
angularity on the crank all joining together to produce more power.
Sometimes the whole is greater than the sum of the parts... could this be
the case here?
I grant that this is probably not a trick that will benefit the 5000 RPM
stockers out there.
Regards,
Ray
At 09:06 AM 10/5/98 -0700, Steve Laifman wrote:
>My $.02 on rod length, IMHO:
>
>There are always those with their hands in the 'soup' that
>can occasionally come up with something better than the
>chemists. In this case, however, I think the hyperbole about
>rod length attributes more results than the original users
>had desired, intended, or obtained.
>
>It is my understanding, from sources around at the time,
>that this 'rod length' change was made for a much more
>practical reason, and is only a secondary outcome of the
>primary rationale.
>
>The engine modifications that really contributed to more
>horsepower, and thereby load on the rods, caused engineering
>concern about the rod beam's capability of handling the
>extra longitudinal loads. Now making them longer doesn't
>help this, all other things being equal, as they will bend
>even easier. However, all other things are NOT equal. It
>just so happens that Ford's (and maybe others) longer
>versions of their rods ALSO had heavier cross sections,
>allowing their stiffness to be greater. That's the reason
>that the Boss 302 and the HiPo rods are in demand. They are
>stiffer due to either metalurgy, cross section, or both.
>
>The length of the substitute rod was NOT the reason they
>were chosen, it was their cross section, and off-the-shelf
>availability.
>
>Now those facts are verifiable, and meet the test of
>reasonableness and are easily analyzed. BTW: Check your
>'hot parts' catalog and see the beam type rods being sold
>for the same purpose. A quick check on their price ought to
>allow an easy understanding of why the thicker rods length
>was accepted, but not a criteria.
>
>There may be some little known tricks to make up for
>compromise manufacturing that are part of any good
>'wrenches' tool kit, but we really don't have to believe in
>magic to understand mechanical engineering.
>--
>Steve Laifman < One first kiss, >
>B9472289 < one first love, and >
> < one first win, is all >
> < you get in this life. >
>
>
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