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Steve@Rennsport Steve@Rennsport is offline
Registered User
Join Date: Jul 2001
Location: Portland Oregon
Posts: 6,984
Re: How could I not realize that....

Originally posted by Erick
... all 6 upper comression rings were broken?

I really wanted to believe that I was 'in tune' with my car, but if it weren't for the fact that the car was spewing/spraying/leaking oil from the pressure relief valve on top of the oil tank, I would have never known there was an engine problem. I thought that the engine was running great. I believe that I even did 2 track days with the broken rings, based on the over pressure oil leak, without noticing that the engine wasn't right.

Anyway, a leak down test showed very low compression in every cylinder.

So, does anyone want to guess how much I was down on power without noticing?

Stock 3.6L 964 = 247 hp
My 3.6L 964 with 6 broken rings = ??? hp

A dyno test would have shown a loss in low & mid-range torque with all those broken rings. Peak HP is not affected very much depending on many factors,....

Bottom line: you & your engine will be MUCH happier with full compression, but I'd strongly suggest that you figure out WHY the engine detonated hard enough to break the rings and prevent that from recurring.
Steve Weiner
Rennsport Systems
Portland Oregon
(503) 244-0990
Old 08-19-2005, 04:32 PM
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