compression

**emotionalpiracy** · 05-22-2008, 10:03 AM

what the relation of combustion chamber size to compression? i know the smaller the chamber the higher the compression, but whats the equation? the pistons in the shortblock i have should yield 10.5 to 1 compression with stock ls6 heads. (at least thats what i asked them to give me), but im looking to get just under 11 to 1 so i can still run pump gas.

**Spaz** · 05-22-2008, 10:37 AM

Originally Posted by emotionalpiracy

what the relation of combustion chamber size to compression? i know the smaller the chamber the higher the compression, but whats the equation? the pistons in the shortblock i have should yield 10.5 to 1 compression with stock ls6 heads. (at least thats what i asked them to give me), but im looking to get just under 11 to 1 so i can still run pump gas.

you can run pump gas with 12.1 comp...

http://www.csgnetwork.com/compcalc.html
calculator...

**Mr. Luos** · 05-22-2008, 11:12 AM

Originally Posted by Spaz

you can run pump gas with 12.1 comp...

I wouldn't recommend it though.

I use this calc. myself. Set-up for the LSx.
http://www.c5frc.com/calculators/Com...Calculator.htm

**Spaz** · 05-22-2008, 11:25 AM

Originally Posted by Mr. Luos

I wouldn't recommend it though.

I use this calc. myself. Set-up for the LSx.
http://www.c5frc.com/calculators/Com...Calculator.htm

i wouldn't either... but there are some people doing it for DD and then using race fuel when they get to the track...

**vaticano** · 05-24-2008, 10:00 PM

I just ordered some pistons w/+10cc dome. I should be at 13:1

**emotionalpiracy** · 05-29-2008, 11:16 PM

well im just looking for the highest compression that i can get the most power and efficience with 93 octane; which i thought was 11. i looked up all the part numbers for the stuff thats in my shortblock to double check. pistons are -6. according to lingenfelter those pistons with a 4 inch crank and 64 cc heads make 11 compression. according to that site from mr luos it would be 11.3. only variable there would be the gasket thickness i suppose lingenfelter didnt calculate that.