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Jan 15, 2006 | 09:18 PM

White_LightningZ

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Compression

what are the postives/negatives of running an 11.6 to 1 compression ratio?

Is this safe to do on pump gas (93)?

Jan 15, 2006 | 10:18 PM

dhdenney

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From: Monticello, Kentucky

I've heard of higher CR's run on the street. Wish I could go back and do it again. I would have done 12 or so. Oh yeah, make sure your cam is set up right for your CR and that can determine your ability to run the higher CR's. I'm not gonna try to explain cuz I'm not sure myself. Leave that to the grinder.

Jan 16, 2006 | 04:55 AM

jimbob

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Quote:

Originally Posted by White_LightningZ

what are the postives/negatives of running an 11.6 to 1 compression ratio?

Is this safe to do on pump gas (93)?

No problem......if you pick a big enough cam....

I run 12.5 to 1 SCR. DCR is 8.77 with my cam. It runs fine but tuning is real important to keep real knock at bay. I have run 11.5ish SCR with some small cams so, I would not worry about the DCR as much in that range. Anything with a intake closing point of (ABDC 68) or higher number should work fine with 11.6 SCR on a 350 cube... If you don't have the greatest heads in the world you can even get away with more DCR up to 9ish is no problem. VE becomes the issue here on how much an engine will tollerate with that high of DCR, especially in the max torque region.

Last edited by jimbob; Jan 16, 2006 at 05:18 AM.

Jan 16, 2006 | 05:40 AM

TwoFast4Lv

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From: LT1 land...the "409" of the 90s!

12:1 here. We are progressing slow on the tuning ...on purpose

it is a Time filler as most shop cars are

Jan 16, 2006 | 03:32 PM

White_LightningZ

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so I would definately need a new cam? what is the smallest I could go?

Jan 16, 2006 | 06:50 PM

99.9percenter

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Quote:

Originally Posted by White_LightningZ

what are the postives/negatives of running an 11.6 to 1 compression ratio?

Is this safe to do on pump gas (93)?

LT1 are very Good at running higher than normal compression ratios. At 11.6 You will gain 10 horsepower. Better torque,better throttle response. Better fuel mileage. Your engine will run cooler. On the down side a blower might be hard to use on pump gas. Nitrides of Oxygen will increase. Running 86 octane might make you nervous.

Last edited by streetbad; Jan 20, 2006 at 08:52 PM. Reason: spelling

Jan 16, 2006 | 11:02 PM

00Z-28-LT1

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i have 12.5-1 comp. on a hot cam. 93 octane with good tuning, no knock

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Jan 17, 2006 | 07:21 AM

cartmanchevy

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From: Minnesota

11.6 will have no problem with 93 octane. LT1s can have a higher compression because of the aluminum heads and the reverse flow cooling helps with detonation.