mikesz

So I'm trying to figure out the DCR of this combo. It's a running driving car that I'm thinking about buying but the DCR is coming out to 8.621. I'm trying to figure out if the car is running race gas or I'm doing something wrong.

LS1 with unported LS6 heads and a comp cam 228/232 112. Intake closes at 46 degrees. Below are the specs I've used with this calculator. http://www.kb-silvolite.com/calc.php?action=comp

Thanks for any help!

Mike

Head Volume: 64
Piston head volume: 1 (account for rings, 0 would make it worse)
Gasket Thickness .052 (guess)
Gasket Bore 3.938 (guess)
Cylinder Bore 3.898
Deck Clearance -.005
Stroke 3.622
Rod Length 6.098
Intake closing point + 15: 61

redtail2426

iTrader: (10)

you can run regular 93 octane with 8.62 just fyi

Killer5.3

iTrader: (1)

Unless it has a dome piston I don't believe it is anywhere close to that with a 64 cc chamber and that LSA. I bet it is more like high 7 to very low 8:1

mikesz

The cam has XER lobes, guess I should have posted that. I think that explains why the intake closes so early and the DCR is so high, but I'm very new to this. The seller did say he runs 93 octane in it. I didn't get a chance to ask if it was a requirment or he just preffered it.

The deal had a meltdown anyway on this very site https://ls1tech.com/forums/parts-cla...l#post16027009. Would be good information to have for the future however.

Thanks for the help!
Mike

Killer5.3

iTrader: (1)

The XER lobe is just a fast ramp rate that opens the valves quicker. I think you should probably get with one of the sponsors on here to spec you a combo that way you won't have any problems. That cam would clear easily with a 64cc chamber head. I think your math is wayyy off on the DCR.

black00ssFL

iTrader: (24)

8.12:1 DCR.....you're fine, a little low for performance if anything.