Hi,

I have bought LS7 engine which has ls2 heads. One head is damaged on chamber by the previous engine damage. Engine is now in pieces. I have almost everything to build engine. I am missing ECU(i have GTO engine harness)and intake manifold etc. I am on budget so i prefer orginal gm parts and planning to build 500-600 hp engine.

What i have read on this forum. Orginal GM LS7 heads are the best to flow but they can cause serious engine damage. What if i buy used LS7 heads and rebuild those whit new valves and valve guides. Where to buy good valves and valve guides?

LS3 heads are quite good also, maybe these would be okay?

LS2 heads. I have now one good one and one whit damaged chamber. Previous owner got them in machine shop to rebuild but i think there is still litle bit edges which can cause knocking. How good LS2 heads are in LS7 block? These would be cheapish solution but will i get whit these over 500hp?



PS. Sorry about bad grammar, i am not native english speaker.

 

You can find LS7 heads for $1,000-1400 that need to be redone. Meaning new s/s exhaust valves (the factory ones are prone to failure), some new valve springs ($300 parts), and most likely a deck resurface $80-100 for the pair, and valve job with new valve guides. You will be into them for probably $2K+.

That should get you going and these heads will out flow the LS2 heads by a mile. You also need an LS7 intake manifold; however those can be purchased for $200 or so used.

corvetteforum.com is a good place to look for LS7 parts

 

I would get a set of trickflow or AFR heads and put them on.

 

TFS 245s or AFR 245s.. no valve dropping or guide wear to worry about.

 

Might be good to post in the right forum next time too

 

Bang for the buck, you could go with ported LS3 heads and intake since you're starting from scratch.

 

From my understanding.. The Ls7 style heads will carry more power up top than the cathedral heads.
Texas speed offer the PRC Ls7 heads within a very good pricing ranges, assembled with race TI or hallow stem valves that won't break and screw your engine.