924Board.org

924_fan · Guest

I have the engine on a stand with the head off. How can I tell what compression ratio pistons are installed?
Thanks.

Smoothie · Guest

My little Porsche Tech Specs book says '78-'79 924XG(USA & Japan) and 924XE(Calif.) all have an 8.5:1 compression ratio.

924_fan · Guest

Thanks.
What I'm trying to find out is how to tell what pistons actually are installed -- to tell if a previous owner changed them.

Joes924 · Guest

Open your Haynes to page 49 ..Get a rule that reads in mm and you might find outtheres a whole mm in diff. sizes .
That wont tell you if they were but it will tell you if its an ovorbore.

_________________
Its my 924 ..and I like it ...and yes its getting faster/ 1979 924 Joe

[ This Message was edited by: Joes924 on 2001-10-11 03:31 ]

Guest · Posted: Thu Oct 11, 2001 5:06 am Post subject:

I can tell you this...The pistons in my engine that are posted in the parts for sale topic are 100% 9.3:1 ratio plus .020 oversized. Put that with a hot cam and you will be pushing 135hp, but if you like your 95hp engine I can't help you. I am just getting ready to ship Joe Danka my used pistons that came out of the engine ..standard bore 9.3:1 ratio.

[ This Message was edited by: ADAM!! on 2001-10-11 05:07 ]

Joes924 · Guest

There you go Adem and I am going to stick them with a hot cam .