6.0 build
Thread Starter
Staging Lane
Joined: Jul 2011
Posts: 67
Likes: 0
From: golden city, mo
6.0 build hey guys some of you might have seen my other thread but i have my ls1 out and the 6.0 ready for whatever i plan to do with it. i want to run the 317 heads but i want to bump compression up a tad, being a lq4. i thought about buying a set of flat top speedpro forged pistons. are they good or you have any other brands that arent crazy expensive? also plan on milling the heads a tad. the engine has about 170,000 on it but it was all highway so im not sure if maybe a hone then new rings and bearings would be a good idea. its not knocking or anything though. or should i just put a cam in it, have the heads milled and run with it? ugh soo many opitions........ plz help. btw this car ill probly see maybe 150 shot. i dont wana go all out crazy on the engine but i want it to be a quick street car
TECH Resident
Joined: Sep 2009
Posts: 859
Likes: 2
From: Frozen Tundra, WI
A good cam (less than 230 duration for the street) is going to give you the most bang for the buck. The difference between an LQ4 dish and flat top LQ9 is .4 in compression so it is not a massive jump. I have heard that nitrous does better with lower compression so you are going to have to give that some consideration.
Last edited by Paul57; Dec 23, 2011 at 06:32 PM.
TECH Resident
Joined: Sep 2009
Posts: 859
Likes: 2
From: Frozen Tundra, WI
Here is a calculator to have some fun with... http://www.csgnetwork.com/compcalc.html
I was getting about .8 in compression going from a 317 to 243 head (with flat tops) which is the route I would choose. You could save money on the pistons going that route.
3.622 stroke, GM MLS head gasket is .051 thick and 4.020 bore, Piston deck is about -.006, 317 combustion chamber is 71cc and 243 is 64.5cc, sorry I don't know what the dish is on the LQ4.
I was getting about .8 in compression going from a 317 to 243 head (with flat tops) which is the route I would choose. You could save money on the pistons going that route.
3.622 stroke, GM MLS head gasket is .051 thick and 4.020 bore, Piston deck is about -.006, 317 combustion chamber is 71cc and 243 is 64.5cc, sorry I don't know what the dish is on the LQ4.
