OK, TEA S2 unmilled 5.3 L heads
63cc chambers

Lunati 382 stroker w/8cc dished pistons

I've been told the 5.3L heads w/out milling will bump my compression to 10.8:1 on a stock LS1

the Lunati Kit advertises bumping compression to 10.6:1 on a stock LS1

So I tried various formulas:

1: 10.8-10.1 = .7 + (10.6-10.1) = .5 , .7+.5 = 1.2 so 10.1+1.2 = 11.3:1 compression

Then I tried the static compression formulas listed in another thread (http://www.grapeaperacing.com/GrapeA...ccompratio.cfm)


(r2 × pi) × length

Stroke = 4.00
Bore = 3.898
(3.898/2)^2 * 3.14159 *4.00 = 47.73458766236
47.73458766236 * 16.387 = 782.22668802309332 CC cylinder volume

Chamber Volume:
63cc chamber
8cc reliefs
3.898" bore
.040" gasket

63+8+x (I assumed x is ~5cc ?) =76cc

Wasn't quite sure how to calculate the space the gasket takes up (also not sure if the gasket size is correct? stock size gasket)

so using:
Static Compression Ratio = (S+C) ÷ C

Where S = Total Swept Volume and C = Chamber Volume

so, (782.23 + 76)/76 = 11.2925 which also shows 11.3:1 compression

So am I right in assuming my 382 is running w/11.3:1 compression? (just wanna verify my math... )

 

Gasket volume is just like the Cyl Volume (but much thinner). 10.16 bore (for 4" gasket bore), 0.1016 thickness (at .040). Basically 8.24cc gasket. You still have one unknown in your formula - The piston sticks up out of the bore on a LS1, so subtract that from the gasket thickness for easier calculation. If it sticks up .08 then take it out of your .040 gasket for a total .032 thickness. That lowers your gasket volume to about 6.8ccs.

I'm coming out with 11.05 using metric numbers.

Are you going to have the cylinders honed?

 

Cool, i just wanted to make sure I didn't end up getting a crazy compression (read a post where a guy got like 12.7:1 compression w/a similar setup... but he musta had his heads milled)

The motor's already built... i got a killer deal on a stock bore 382 kit so I used that and just had the cylinders cleaned up (used a low mileage LS6 block)