Max compression on a street car?

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May 8, 2008 | 09:44 PM

#41

sheikss

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From: columbus GA

I'm at 12.38 to 1 with no problems.

May 8, 2008 | 09:53 PM

#42

James Montigny

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Quote:

Originally Posted by projekt70chevelle

Is there actually a measurable gain in power by raising the c/r one point (10.5:1 -> 11.5:1)?

That's no small change.
Should be significant if you can do it without inducing timing retard.
Worth a good 20rwhp up top even with a mild cam.

Hell, just switching to thinner head gaskets is worth 5.

FWIW, I'm up around 12.1:1 with my new setup (zero-decked -4cc pistons) on pump gas.
I had 11.3 with the previous setup (stock deck and pistons) on pump gas.
Both setups use a cam with a very aggressive LSA.

May 9, 2008 | 10:43 AM

#43

OutlawZ

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From: Cali

Just my .02 on this.... I think 12:1 is when you need to start looking into running premium fuel if you plan on beating on it....

If you're just running back and forth to the store then yeah run pump gas..... if you are going to the track run 108 or 110 or other premium race fuel. It's cheap insurance.. (Errrr rather expensive insurance at 10.00 a gallon)... but still worth it...

May 9, 2008 | 03:51 PM

#44

Lt1junkie

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From: Hampton Roads VA

Quote:

Originally Posted by OutlawZ

Damn cam cost $10 out in cali? It is like $5.99 here on the east coast

May 10, 2008 | 04:05 PM

#45

James Montigny

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Quote:

Originally Posted by OutlawZ

Just my .02 on this.... I think 12:1 is when you need to start looking into running premium fuel if you plan on beating on it....

Depending on the cam and tuning, yeah.
I would not tune a DD for race fuel though,
I'd either run a separate tune at the track or not run race fuel at all.
I do however tune for premium pump gas (92 Octane in this part of the country)

May 14, 2008 | 05:41 PM

#46

projekt70chevelle

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Is it safe to say that i should have no problems with 11.2-11.5:1 compression, cc503 cam (114lsa), 100 wet shot, and 2 degrees of timing pulled (via madz28 tuning)?

Aug 3, 2008 | 03:00 PM

#47

C_Rules

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From: NYC

I started this thread like 6 months ago and now 4 1/2 months later after sending my motor to get done I got it back and the car is running. Its a 385 LT1 approx. 11.4:1 SCR and 8.79:1 DCR. I haven't hooked the laptop to it yet since i haven't been able to drive it normally. I'm all out of alignment. I put a tubular k member and lower adj a arms and I need to get those setup properly. Hopefully this Monday I'll take it to get done. Once its aligned I'll take it out for a thorough drive and hook up the laptop to it to see if it's knocking. Otherwise it feels fine and I don't hear any knock but that doesn't mean there isn't any. I'll keep you guys updated.