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[Shurick]

Actually I'm rebuilding a 31/01 engine. What do I need to upgrade to 8.5:1 c.r., like 31/03? I think, that the higher pistons will resolve the problem. But there is one more problem -- the ignition. 31/01 std ignition can led to the detonation.
In my plans are the 951 or Audi 200 intercooler installation and boost pressule up to 1 bar. It must produce nearly the 250 bhp, but how to kill the detonation?

[ This Message was edited by: Shurick on 2002-10-17 06:47 ]

[Zuffen]

Do a search on the net for the Volvo APC system, there is a site which explains how to retrofit a knock unit into a none knock car. It might help.

Also water injection and water cooling of the intercooler will help keep cahrge air temps down.

But unless you really are going to be boosting higher than 1 bar, even at 8.5:1 your fine with an intercooler

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[924 turbo]

Just out of curiosity, what "problem" are you trying to solve by switching from 7.5 to 8.5 pistons?

[Shurick]

The car looks dead on low RPM...

[924 turbo]

Ok, you're right, that will solve the problem!