how much h/p will I gain from 241 to 243 Cylinder head ??

[jinouk67]

Just like the title says, How much more h/p gain will I have on my car if i install 03 zo6 243 stock heads to my gto. See below on current moda.
How much addt'l h/p can I expect if i get the heads ported ?

[tylerdurden1]

Are you keeping the cam as is? Just the ported head swap for now?
Since you own a 04 ls1, is the 05 model (6.0L) have the 24x crank sensor wheel or is it the 54x wheel? Just curious to ask a Goat owner. I really like those vehicles. I would not mind owning a larger coupe w/ heavy duty suspension. (nice comfortably seats)

[jinouk67]

Are you keeping the cam as is? Just the ported head swap for now?
Since you own a 04 ls1, is the 05 model (6.0L) have the 24x crank sensor wheel or is it the 54x wheel? Just curious to ask a Goat owner. I really like those vehicles. I would not mind owning a larger coupe w/ heavy duty suspension. (nice comfortably seats)

See my Signature for full the mods. I have comp cam 222/224 566/568 112lsa.
Yes 05 has 6.0L motor vs 5.7L.

[RedMetal]

If you are just make a swap from stock 241's to stock 243's then 15-20rwhp would be a "safe" expectation..... maybe use a cometic gasket set to get the CR up a bit and the quench better for some extra power.

[Kup98ss]

would those heads eat gas or be about the same?

[Eddie 70]

would those heads eat gas or be about the same?

I would think that it should not make much of a difference in gas mileage, if any at all. This is all dependent on your right foot of course.

[Frost]

20 to (believe it or not) 35rwhp with the cam and mods that you have already. I didn't tune the car that picked up the 35, but I saw it on tech with the graph. 20-25 is quite common though.

[jinouk67]

If you are just make a swap from stock 241's to stock 243's then 15-20rwhp would be a "safe" expectation..... maybe use a cometic gasket set to get the CR up a bit and the quench better for some extra power.

Who sells the cometic & what is the cometic gasket size i can use to up the cr w/o having the ptv clearance ?

[WEZONIT]

I will be using a Cometic .040 Gasket on the setup in my sig. That should put my compression somewhere around 10.9 -11.0 to 1. I bought everything from texas speed. Without a porting job I think you might see 15-25 RWHP with stock 243's.

[jinouk67]

I will be using a Cometic .040 Gasket on the setup in my sig. That should put my compression somewhere around 10.9 -11.0 to 1. I bought everything from texas speed. Without a porting job I think you might see 15-25 RWHP with stock 243's.

The stock 243 head compression is 10.5:1, If i go go with the same cometic gasket as u that would give me same comprssion as yours. Base on my cam exhaust 566/568 i should be fine with the ptv clearance right Z?
What came with the kit & how much is it ?

[PFM]

12-15hp would be pushing it.

[Frost]

12-15hp would be pushing it.

maybe for an unlocked automatic... have seen (tuned) 26rwhp out of a used stock set (stock minus 918 springs) on an M6 car with a small cam, and 22rwhp out of an M6 with an intermediate sized cam (233ish intake 237ish exh). They have suprised me.

[RedMetal]

I agree with Frost... I have seen more than once M6's picking up a solid 20rwhp with a small cam and tuned, and you can squeeze a little more out of it if you run the 0.040 cometic gasket kit as WEZONIT stated. That size cometic should give you an extra 0.30-0.40 boost in the CR results...10.8-10.9. If you have a little extra cash 100-200 bucks get them milled down to 61-62cc and use the cometic for a CR of around 11.3-11.4 which is easy to run on 93 octane.

With that compression you could "probley" run a 228'ish .580/.580 112lsa..... but that is just a guess!! You need to talk with your shop/tuner.....