4.8 to ls1

[ff_jeff]

Were talking about pp the 862s rite? Wow, always thought the 799/243 were the next best thing to l92 heads. I wonder what the compression would be like with the smaller chambers of the 862s?

here LS1 Info and Specifications - SMOKEmUP.com
the stock 243 heads are nice. But many people use the 5.3/4.8 heads and port them. If you have a set, and jus pay for machine work, you dont have to buy the $500 243 heads, then machine them. at 61cc stock, you can even mill a little more off. 243 heads are 64.4 cc.
a ported 243 should out flow a ported 5.3, but you will pay for it. Check out prc heads, tx speed heads ect. They all sell ported 5.3 heads. I think their 5.3 flow like 300 at .600 lift.
with 61 cc heads, and a stock head gasket thickness (.051) you should be at around 10.75 CR. or so. With a .041 gasket right at 11.0cr.