"Jerry J. Wass" wrote in message
...
Anybody got a Cont. parts book for the IO-470 series engines--I have
piston #--
need to know the compression ratio it produces---#627738

Thanks

Jerry


Jerry, the old parts catalog I have for the O-470 shows this piston as 8.6
to 1 compression ratio.

Lower compression pistons on the O-470 are 8.0 to 1 CR.

http://dougnlina.home.mindspring.com/PDFs/IO-470.pdf