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Sboxin Sboxin is offline
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Join Date: Jan 2007
Location: Phoenix, AZ
Posts: 858
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Quote:
Originally Posted by r lane View Post
I think 100 octane is not enough for 12.5 to 1. I also think that with that compression, the heads wil l bow. The stud spacing compared to a 3.0 or 3.2 is greater. Don't know what you can do about that other than lowering the compression.
r lane - -
Thank you for your response. I agree that the 964 heads are a weak link in these race engines and Steve Wong said so before he started the Dyno tune process - that's why he tuned for a lower HP than the engine could produce at max power settings - - we dyno at max 277 RWHP and 255ftlbs RWT and have had the same set up for 10 years running this engine with no head damage. The 100 oct fuel is more to cool the heads than to get max HP from the 12.5CR pistons.

We will know more after getting the fuel injectors tested and cleaned - - and when our engine builder talks to Henry about the heads lifting with the Supertec head studs.

Regards,
Roy T
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Old 05-27-2022, 07:54 AM
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