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Old 07-09-2007, 03:18 PM
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Default CR and Fuel

Does anybody know what the highest C.R. one could run if using 93 octane fuel? I know past a certain point one would have to bump up to race fuel. What is that point? I ask because in my head selection, I want to get as high as compression I can get.
Old 07-09-2007, 05:23 PM
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What are the specs on the cam you plan to run.
Old 07-09-2007, 06:06 PM
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I'm at 11.0 : 1. I believe you can go to 11.3 without a problem on 93 octane.
Old 07-09-2007, 06:11 PM
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I would check with the company you are getting the heads from and your tuner. I just checked the pm I got from Tony Mamo when I was doing my AFR's. He said 11.47:1 was doable on 93 octane with my cam. That would be AFR 205's milled 0.030 with a 0.040 cometic gasket.
Old 07-10-2007, 12:07 PM
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The cam is a LM G5X2 112 and the heads are going to depend on how high I can get my compression.
Old 07-10-2007, 12:37 PM
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On a stock shortblock with un-touched pistons using a .040 gasket....

If the cam has 4* advance you can run 62cc chambers and your SCR/DCR would be 11.38/8.77

If the cam has 2* advance you can run 60cc chambers and your SCR/DCR would be 11.69/8.85

With both situations above you can run 93 and thats on the safe side. Keep in mind this is my opinion and what we can get away with here in texas assuming we keep the car cool. My personal setup will be a bit more agressive.
Old 07-10-2007, 09:40 PM
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Thanks Donaimian. I was thinking about chambers somewhere in the 50's cc. I did not know if that was pushing it. Im not against running fuel in it at all. Would be a strictly weekend car if that was the case since race fuel is over $5.00 a gallon here
Old 07-10-2007, 09:44 PM
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also thanks davered00ss
Old 07-11-2007, 12:09 AM
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Originally Posted by LS1Z28_98
Thanks Donaimian. I was thinking about chambers somewhere in the 50's cc. I did not know if that was pushing it. Im not against running fuel in it at all. Would be a strictly weekend car if that was the case since race fuel is over $5.00 a gallon here
You can go into the 50's, my recomendation was somewhat on the conservative side.




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