00pewterz

iTrader: (34)

I am trying to find out how much I would have to deck a set of 241 heads to get 10.5:1 on stock ls1 pistons. Also would I have to worry with valve clearance on a .580 lift cam?

LS1-450

iTrader: (33)

Aren't 241's already 10.5:1?

00pewterz

iTrader: (34)

Not positive but I thought that an ls1 with 241s was 10:1 but I could be wrong.

NemeSS

iTrader: (127)

it will depend also on what gasket used, piston out the bore measurement, along with mill

02*C5

iTrader: (1)

if its an LS1 241's its 10:1 if its an LS6 243's its 10.5:1. Very little like .001 will get you somewhere around 10.5 depending on the chamber size. I had mine done .003 w/ 59cc chambers and I was running 11.5:1 w/ a 600 lift in and out cam.

Damian

iTrader: (89)

.015 will get you where you need to be.

FYI LS1s are 10.1:1, LS6s are 10.5:1.

The lift of your cam won't matter as much with PTV clearance, as duration and ICL. Whats the duration and LSA/advance on the cam?

novaflash2002

iTrader: (51)

i belive you mean .010, and yours being milled .030. for every .006 that is milled its approx 1cc.

02*C5

iTrader: (1)

yeah sorry got the decimal point wrong. your right

hammertime

iTrader: (1)

Another option would be to run .040 thick gaskets (I believe stock is .053) for almost the same results without the machine shop labor. Of course that is assuming your deck surface is square and free from imperfections.

General rule of thumb is 1cc for every .006 removed on LS heads. Chamber size & shape will change that figure for different engines though.