Hey i have a 99 ls1, and on this forum i found a good deal on some stock heads. they are casting 12562317. i've read up and it says they're from a 6.0L '01+ engine. the chambers are 71cc instead of the 66.7cc on my current heads. I was wanting to buy them and and maybe build them up in my spare time over a few months and then swap them out when i get a new cam.

So my question is, first of all, i need to know if it will fit alright on my camaro! Then my other question is will it be worth the buildup horsepower wise?

 

anybody?

 

There are 2 port designs on 6.0 heads. The LQ9 heads have the same port design as the LS6 heads, so they flow better than the LS1 heads. These have a D port exaust. Articles/books have said the LQ9 head ends in 035, LQ4 = 317, but if you do a search on silveradoSS.com, those guys say their LQ9's have 317 heads. So I think the thing to look for is the D ports.

They will bolt on to an LS1, but the drop in compression will probably offset any gains from the extra flow. So probably not worth the swap on a stock 346. These heads would be great on a stroker. I'm thinking of building a 383 LS1 or a 6.0 based 402, and these heads would be a good low buck choice. But the original engine in my car is running like a champ, so it would be a shame to yank it.... and I'm not as crazy as I was in my misspent youth.

 

ya thx for the info, i posted in advanced tech and got the same thing from them. he said dont do it unless i'm going forced induction. so i think i'll hold off till i find some used camaro heads and build those in my spare time.