CA 91 octane and 11:1 CR ?

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Jun 11, 2005 | 10:19 AM

brians98ss

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CA 91 octane and 11:1 CR ?

Is there anyone out there running around 11:1 compression and using 91 octane? If so, have you experienced any problems with detonation, pinging, etc.?

Hopefully will be buying heads soon and am still undecided if I want to get them milled or not for increased CR.

Thanks for any replies.

Brian

Jun 11, 2005 | 07:50 PM

M6HuggerSS

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when i did my H/C i was told 11:1CR gives some people troube with just 91... so i just milled mine to a 10.6:1 CR (64cc)

and zero probs.

Jun 12, 2005 | 12:51 PM

Rick@Synergy

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I have done up to 11.5CR with 91 and no problems. ITs in the tune and the camshaft.

Rick

Jun 12, 2005 | 12:53 PM

BlownChevy

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Quote:

Originally Posted by Rick@Synergy

I have done up to 11.5CR with 91 and no problems. ITs in the tune and the camshaft.

Rick

Jun 12, 2005 | 08:30 PM

brians98ss

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Quote:

Originally Posted by Rick@Synergy

I have done up to 11.5CR with 91 and no problems. ITs in the tune and the camshaft.

Rick

Rick,

The cam I have now is the TR220 on a 114 LSA. Do you think there is enough overlap with this cam to support 11:1 CR assuming a good tune?

Thanks.

Jun 12, 2005 | 08:53 PM

M6HuggerSS

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that cam will work fine but why not go a little bigger?

Jun 12, 2005 | 10:32 PM

Rick@Synergy

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Overlap has nothing to do with compression. Its all about valve event timing. When does the intake valve close is what you should look for. That will help with the higher compression.

Rick

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