Help squeezing some hp from my stroker
 

Have a 05 GTO with a TSP 404 short block. Picked it up from a buddy for a good price. Plan to pull the motor and swap into my 96 impala.
https://cimg5.ibsrv.net/gimg/ls1tech...37ad09ebb2.jpg
https://cimg0.ibsrv.net/gimg/ls1tech...e0a0b90202.jpg
has ported 243 heads and ls6 intake. Made just shy of 500hp when last dyno tuned. When i pull the motor i plan on swapping heads and probably the intake. Any suggestions? Was looking at prc 237 heads as recommended by tsp, dont know what to do intake wise. Not any form of an expert with ls engines, especially cam/head/intake matching, so kinda looking for a little help. Thanks

I had, but was told i wouldnt see any gains over the 237s, hence this thread.

^^^^^^

Our impala club runs a national event every year. During its course we will run a road course, autocross, and drag race. Most the time i use it for summer cruising, but I do enjoy autocross 3-5 weekends outside of our club event per year. I dont know what you consider a high rpm engine, but i would like the heads to support whatever the engine can throw at them
https://cimg3.ibsrv.net/gimg/ls1tech...fc32415be3.jpg

400+ cube, ideally what KCS said a set of mildly ported LS3 heads, matched cam, plus either an LS3 intakeor Radius Rod mod'd LS3 intake. My 416 with a similar set up makes 400 wheel foot pounds of torque at 2,800 rpm and the hp peaks around 6,000 rpm - fun street car set up. 404 could do about the similar low end torque and powerband.

Is there a vendor or brands that you guys prefer for LS3 heads? Are the ported GM performance heads enough?

For cost and bang for the buck:

260cc Precision Racing Components (PRC) from Texas Speed...……. https://www.texas-speed.com/p-4010-p...der-heads.aspx
260cc Air Flow Research (AFR) Mongoose...……… https://www.airflowresearch.com/260c...cylinder-head/
255cc Trick Flow Specialties...………. https://www.summitracing.com/parts/t...-c01/overview/

BTW.....you have PM.

KW

the prc head with fast 102 will get u a decent power gain. Plus with the 62cc heads ul also get a bump in compression. i saw a 58hp/ 48tq gain swapping the fast 102 over the ls6 intake. i also run a prc head. This was on my ls1 tho but should still produce similar results.

Ok, so im still working with this gto/engine. Under a time crunch to get the car done for an event in july, so i had decided to hold off on swapping heads and roll with the 243. Had quite a bit of engine noise that a couple of owners have tried to solve. Opened up the valve covers and did some inspecting to find this

https://youtu.be/BVHb4I3G7RA

Ordered comp's press in trunnion bearing kit and installed. Didnt have any play in push rods. They were a hardened set, all straight. Thought i had found/fixed the source of the noise until i got it back together and it was just as loud. Took this video earlier.

https://youtu.be/B-qbboqAfKs

Seem to be finding conflicting info on noise from big cam/dual valve springs with thin walled headers(kooks long tubes)

normal? Abnormal? Rip the heada off?
​​​

Cam you have is pretty mild for a 404" stroker. A well ported FAST 102 with a 92-102 TB will pick up 30 HP+ @ Peak,
and more importantly 20+ lb' throughout your torque curve vs the LS6 which is choking your combo severely.
Changing the heads without changing the intake would Choke even greater and lead to very dissappointing
results.

has a 102mm TB on it now. currently researching heads/cam/intake combo to replace with. more pressing at the moment is getting the swap done from the gto to the impala. have to have it done, and reliable for the end of july. have a whole rear end to rebuild as well as a bunch of other misc.

How would that cam work if you put LS7 heads, fast 102, 102TB, with 1.8 rockers?

Put on what? OP has a 4.010" Bore.

Standard LS7 (non small bore) Heads need 4.070" Bore to physically fit,
and ideally 4.125" for optimum performance. LS7 Cams most often have +12* up to 16* and more
Exhaust split on the cam due to the low E/I ratio.

Oh dang, didn't realize his bore was that size, I saw the cam specs and my thinker acted up, I have a cam a little less intake duration and a little more exhaust duration 231 246, I have LS7 heads, little more bore 4.155 so I was just curious what the power might be like. But now realize not a good comparison. Should have read a little more thorough.