Recommend cylinder heads?

[WHAMMO]

Bowhite I'm glad you are stepped in cause I don't think compagnies would sell heads for 0-10hp. Your results are excellent!!

[KW Baraka]

Originally Posted by weSS1LEy

Won’t do it for less than 30hp. Looking for increased flow, increased compression and safer valve angle. Anything else I need to consider? AI, AFR, PRC, ...

I have PRC 260's on my stock displacement LS3

I have AFRs on my stroked (427ci) LS3.

Best of luck.

KW

[KW Baraka]

Originally Posted by WHAMMO

…..There's like 2-3 guys in recent threads saying they gained 0hp with ported aftermarket heads. But gained 20-30 in the mid........

I'm one of those guys....sorta.

PRCs on my 6.2 only gave me about 11 peak hp to the wheels....but from about 2500 to 5500 RPMs, I was in the plus 25-30 hp range and plus 20 tq range.

Compression was bumped up about .6, to about 11.3:1

This was with a 229*/242* cam that was already installed.

Performance increase is VERY noticeable.

KW

[frey.199]

Originally Posted by WHAMMO

Higher compression will be the real big gains, and power in the mid range I guess. Not much of you're staying same comp ratio.

There's like 2-3 guys in recent threads saying they gained 0hp with ported aftermarket heads. But gained 20-30 in the mid.

I'll just freaking go all out on lightly ported stockers/notching/high comp ratio and spin them to the moon till it blows.

I think with stock manifold and medium cam it's not much of a gain, except better PTV clearance
With higher comp ratio...

What all is involved in increasing compression ratio? What do you change?

[go_go_gadget88]

I am running TSP ported stock heads with their stage 3 cam. I think mine runs damn good, but I couldn't tell you how much came from cam and how much came from heads. I know it put down well over 500 to the wheels on a mustang dyno, so that was nice! It gained over 100rwhp from the cam/head swap...but I am sure the cam was 75% of that

Either way, no regrets for the money spent. I question if it would be worth it to jump to an aftermarket casting, but that seems like a lot of money to maybe pick up another 20 or so

[lazerlemonta]

Originally Posted by go_go_gadget88

I am running TSP ported stock heads with their stage 3 cam. I think mine runs damn good, but I couldn't tell you how much came from cam and how much came from heads. I know it put down well over 500 to the wheels on a mustang dyno, so that was nice! It gained over 100rwhp from the cam/head swap...but I am sure the cam was 75% of that

Either way, no regrets for the money spent. I question if it would be worth it to jump to an aftermarket casting, but that seems like a lot of money to maybe pick up another 20 or so

Real benefit is PTV clearance with aftermarket castings. You can get the valve events much more aggressive and still have lots of room. I gained 40 from an intake swap lol 80 from the head cam.....

[WHAMMO]

Originally Posted by KW Baraka

I'm one of those guys....sorta.

PRCs on my 6.2 only gave me about 11 peak hp to the wheels....but from about 2500 to 5500 RPMs, I was in the plus 25-30 hp range and plus 20 tq range.

Compression was bumped up about .6, to about 11.3:1

This was with a 229*/242* cam that was already installed.

Performance increase is VERY noticeable.

KW

We're you running the stock intake?

[Yellow 1]

GMPP do a great value package of cnc-ported heads and a mild cam that will get you 45-50 hp. Can't remember part # of kit but it's in the GM Performance catalogue. Get some long tubes with that setup and you're cooking.

[dino2012ls3]

I'm glad yall are chiming in cause I'm on the fence bout heads. It seems that for the bang for the buck the PRCs are the way to go. I'm running a bigger cam .236/.242 seems like heads would really wake it up. Would there be any benefit in porting the PRCs or just off the shelf?? I'm assuming with the PRC you're changing the angle so you could run a even bigger cam and not worry bout PTV clearance.

[weSS1LEy]

Gmpp heads cam for 50 hp is ok but I got 55 hp cam only. I’m thinking prc too. Bump in compression

[christianchevell]

Go GPI

………. performance package with the ls7 small bores, other than need for the increased flow from stock already great flowing ls3 heads you should not gain much, talk is cheap.

I priced out lots of heads and their flows and their gains my last build and finally just went with gmpp cnc heads for now, someday when I have the money I will do the GPI heads there are post on here of their gains with their package, most get little form just doing heads, some shave the stock heads which is Dumb and then limit their PTV more. And not just that if they someday want to put the heads on another engine because we can only overhone a ls3 .020....well shaved heads already have material taken off stock and then you add some pitting from them being soft aluminum and cleaning them up they may need shaved/decked for reuse.....

IMO don't expect miracles and you won't get them anyway, Dickey Scoggins fine tunes the Stock CNC heads for cheap, you want to go all aftermarket casting IMO the best I have seen out there for $$$ is the GPI heads....I used to look at mast black labels, etc etc etc etc...…. stuff costs $$$$$ and there are several advantages to the ls7 style head namely the LS7 rockers which would multiple your lift more actually making more power!!!! which for many may mean they just want a milder cam because its multiplied by the rockers ratio...… also a different angle for better clearance for even larger cams...… So in other words just add about .30 to all the lift numbers of your existing cam...

Good Luck , just my thoughts, some day I want them...…
https://gwatneyperformance.com/produ...d-cam-package/

Busy paying down my Brainiac's student loans with her neuroscience degree locked me up for a couple more years as with the wife...… and fixing the house up incase I just up and croak someday.

[weSS1LEy]

So are these ls7 style with a ls3 size bore? I’ve never understood this.

[zz430camaro]

Yes, the are ls7 raised port heads to fit a ls3. Requires a ls7 intake too

[weSS1LEy]

How many hp would this ls7 heads and intake manifold gain? Approx