i have a 2003 gmc 6.0l lq4 with #317 casting heads. dose anybody know of any problems i might run into putting a set of #243 ls6 heads on it? any problems no matter how small. and also, what will be the HP gain in doing this?i am very old school when it comes to motors. im new to the ls and lq stuff, but it looks very interesting. looks like some major HP for little money.

 

I don't think the 243's will flow any better. If you want some power, just mill your heads and get a cam based on your needs with the truck.

 

the flow is the same. but i will be going from a 71.06cc to a 64.45cc head. heads i dont mind doing. but it takes a lot more energy to pull the cam. i found a "new" set of 243 heads on ebay for $250.

 

the 243 are supposed to flow the same put have like a 64 cc combustion chamber wil the 317 has around a 71-72 cc chamber..i would do it, i have an lq4 with ls1 241 heads and im wantin to stick the 243's on it

 

Problems... I can't foresee any. It'll bump your CR a bit, but you'll still be running dished pistons so I believe you'll still be under 10.5:1.

 

yep take your scr to around 10.5 which we all know cams love cr

 

will there be a problem with running regular gas? OR WILL NEED TO GO TO THE SUPER AT $3+ ?

 

the difference in a full tank of 93 and 87 is 5 bucks. 5 bucks we **** away. i wouldnt put 87 in anything i own besides lawn equipment. its just not worth the risk

but yes you would need 93

 

easy for you to say. my truck weighs almost 6000lbs. empty. with a 4.10 rear end at 10.5 mpg. with a 1 hour drive to work. but i did just buy a programer and it should be here this firday. hope to get a couple mpg's extra. also have plans to put a 3.73 ring and pinion in it.

 

lol... you say that like you're the only one in that boat