I'm building a 370 out of an iron LQ4 motor with un milled ported 243's, i will be using the stock crank but i will be going with Eagle forged H beams and forged Mahle pistons with valve reliefs..i wanna know if i'm getting the right Static compression ratio

these are the ones i bought got a deal ($960.00) Tax Exempt through AutoZone


Eagle Specialty Products CRS6125O3D - Eagle ESP H-Beam Connecting Rods - Overview - SummitRacing.com
Mahle LS1314030F04 - Mahle PowerPak Piston and Ring Kits - Overview - SummitRacing.com

^those are the parts i have in my possession, i just got my Tick Stage 2 street heat cam in the mail today as well and it looks killer , (Thanks for the help martin)

here is what i came up with by using the Excel spreadsheet


Can anyone double check that i got my input numbers correct? 11.x:1 compression sounds nice if i can do it (i will be using stock mls gaskets) and im pretty sure the parts man told me the reliefs in the pistons are 4cc cuts

 

Something seems awry here. An LS2 with the factory flat tops ( no reliefs) is only 10.9:1 static with 243/799 casting heads un-milled. I don't know how far in the hole GM's pistons are off hand on one of them.

Those pistons from what I am seeing have a 4 cc dish to them... not a dome. So that number needs to be a negative and not a positive. From TR's site:

-4cc valve relief ;

So you should change that in the calculation.

Otherwise with the pistons 10 thou out of the hole and a 51 thou gasket that does net a 41 thou quench.

The piston dish is the only thing I see wrong. Should be more like 11.5:1 after that change I would think.

 

Are you running the stock piston deck? If so, that 0.010 should be -0.008