Zl1 heads running 15/20 lbs making 900 hp

[Trob85]

Looking at getting a set of new heads for forged 376 with Procharger d1sc. My question is I've heard the lsa heads are great for boost because they're designed from gm for a boosted engines would it be more cost effective to just port and polish the ls3 heads or pick up a pair of lsa heads and just polish them to a smooth surface to create less friction. My goal is 925 to 900 horsepower need input.



........and I already know they're made of a better metal and have a thicker deck I'm asking what have people pushed these too.

[62nalide]

900rwhp plus is not gonna happen with a D1SC if you so get ckose to it will be maxxed out, might wanna look into an F1 and the stock heads can handle that.

[Camarojt]

[Trob85]

No sorry My fault I'm looking for 900 at the crank only so 790 800 at the wheels I'm just trying to get input on rather or not to just switch out the valves or send the heads out to get polished just trying to figure out the best route if they really need ported or not.

[VADER SS L99]

The LSA heads dont NEED ported but they will make more power with less boost if you do port them.

[Trob85]

That's what I wanted to know I already plan on running big boost so that answers my question thanks man Anyone else have any input.

[JLE58]

Originally Posted by Trob85

Looking at getting a set of new heads for forged 376 with Procharger d1sc. My question is I've heard the lsa heads are great for boost because they're designed from gm for a boosted engines would it be more cost effective to just port and polish the ls3 heads or pick up a pair of lsa heads and just polish them to a smooth surface to create less friction. My goal is 925 to 900 horsepower need input.



........and I already know they're made of a better metal and have a thicker deck I'm asking what have people pushed these too.

LSA's have the same Deck thickness as an LS3 head the thicker deck is just a myth ls9's are the ones with a thicker deck.If you already have the LS3's you might as well just use them. At your power you should be fine with the LS3 and your not going to gain anything from the LSA's. If i was going to buy NEW I would get the LSA's over the LS3's.

[VADER SS L99]

Originally Posted by JLE58

LSA's have the same Deck thickness as an LS3 head the thicker deck is just a myth ls9's are the ones with a thicker deck.If you already have the LS3's you might as well just use them. At your power you should be fine with the LS3 and your not going to gain anything from the LSA's. If i was going to buy NEW I would get the LSA's over the LS3's.

Thats actually news to me as well. I read they have a slightly thicker deck and are a better casting. Just goes to show you cant believe everything you read on the internet.

[62nalide]

Originally Posted by Trob85

No sorry My fault I'm looking for 900 at the crank only so 790 800 at the wheels I'm just trying to get input on rather or not to just switch out the valves or send the heads out to get polished just trying to figure out the best route if they really need ported or not.

Oh I see, if you have the $$$ to go with LSA heads go for it. I milled the L92s mostly on the exhaust ports pushed about 22lbs of boost through a T76mm turbo and and Victor Jr intake made 817rwhp 787rwtq on my old truck so pretty sure the LS3 heads will do just fine.

[Trob85]

Yea see this is the problem I've been running into they have thicker decks then they don't they flow better without porting but you should mill the fins on the intake valve the only thing I actually read that everyone can agree on is that it has stronger metal. The only good thing is the fact they really aren't that expensive I can get them from jegs for 460 a head with the valves and springs even though I would need springs for a 675 lift

[JLE58]

Most people never cut one in half. It's a little under 1/2 inch deck just like the ls3. It's a far better casting than an ls3 though and has some improvements in the right spots for sure.

[VADER SS L99]

Originally Posted by Trob85

Yea see this is the problem I've been running into they have thicker decks then they don't they flow better without porting but you should mill the fins on the intake valve the only thing I actually read that everyone can agree on is that it has stronger metal. The only good thing is the fact they really aren't that expensive I can get them from jegs for 460 a head with the valves and springs even though I would need springs for a 675 lift

That's what I don't get. The LSA assembled heads are the same amount as the LS3 assembled heads yet if you were to buy a ported pair you would end up paying $800 more for the ported LSA heads. What gives? Is it just LSA ZL1 tax or what?

[*_ERIC_*]

From what I've been reading is that the LSA heads are cast better and provide better fuel atomization for forced induction.