[Land-speed] dumb Question # 4856 - Wrist pins

[Kirkwood]

Agree with all of the above but the consumer is not the driver on the pin
diameter substitution. It is (or was) the automotive machine shops. Prior to
the recent crate motor phenomena that has put many machine shops out of
business, the major customers of aftermarket engine parts are automotive
machine shops. They have a significant investment in tooling as wells a
set-up time in the ubiquitous SBC. Having one pin diameter means you can cut
tooling inventory but the biggest savings is setup labor. Setting up the
Sunnen rod hone and/or air gauge for one diameter and leaving it there all
day for the majority of the work is profitable. Since engine balance is
usually part of the machining job the pin weight delta is irrelevant.
Economics is the driver and not performance.

Larry Mayfield <drmayf at mayfco.com>
I see a number of  Ford products whether pistons or  rods offered with the
option of using the GM wrist pin diameter. . . . "why switch from 0.912 to
0.927 inch diameter wrist pins?