hey, Ive been in the process over the last few months of getting parts together for my turbo 5.3. Wiseco recently came out with stock bore flat top pistons and according to their site with a 6.125 rod compression ratio is 10.4 with a 61cc chamber. If I were to bolt on a set of ls1 heads, would that be an acceptable way of getting the CR back down for turbo use or should I still consider spending a grand on custom slugs? I dont have any numbers on head gasket thickness cause thats still in the air as far as what Im gonna use but I think the stock MLS gasket is probably gonna be it. I guess on alot of numbers and came up with a CR of 9.3. If anyone can figure out the CR a little more exact than I can Id appreciate it or if anyone has any thoughts on going this route itd help me out a ton cause I know I can just trade my heads for some ls1 heads and be on my way, they get higher compression I get lower compression, win win.

 

243 castings (64cc) and flat top pistons will net 9.9:1 , why not look at a set of 317's?

 

yea 317s have a 72? cc chamber..

 

Ill look at whatever gets me there the cheapest lol. Like I said I guessed on a few things calculating the CR and on ls1tech I found a table saying that stock ls1 heads were 66cc's (maybe I read it wrong) and I guessed on deck height. I was off by .6 but then again thats why I asked. Also the impression Im under is that these will match nicely with an ls6 mani right? I already have one so Im hoping thats the case. Any idea what CR Id end up with running these (cause its obvious I guessed wrong the first time). BTW Im shooting for 9:1 or within a tenth either way

 

241 (ls1 heads) are not going to breath as well as the 243 (ls6/ls2) but the 317's will drop compression and breath as well as the 243's.

 

sounds good to me now I gotta find some. Anyone wanna trade lol

 

these??
https://www.performancetrucks.net/fo...d.php?t=436441

 

ehh those probably need to be surfaced and have a helicoil set in the head. Im low budget but not that low budget lol