Horsepower increase with TSP heads and current T2?
Thread Starter
Joined: Jun 2002
Posts: 669
Likes: 1
From: Amarillo, TX
Horsepower increase with TSP heads and current T2? I have had my T2 cam for a few months now (numbers are in sig.) and am enjoying it.
I have been debating about doing heads for awhile now, specifically the TSP stage 2.5 5.3L heads.
I have seen so many H/C car numbers that range from 420 to 470(all M6 cars) and have to say I am alittle discouraged. I know every dyno is different and every car for that matter, but with such a huge difference across the board, I feel like it is a crap shoot on the numbers I can expect.
I would like to hear from some (Patrick G., Predator, Anyone at TSP, etc.) who could give me a reliable expected HP increase by adding these heads.
I know they are supposed to produce around 50rwhp more, but I have seen where they only get 20-30rwhp.
Is mid 440rwhp and 400rwtq a reasonable goal with just the addition of heads? If it's probably only gonna get 30rwhp, then I will more than likely put on nitrous. I need some reassurance before I drop $1100 for heads and another $600 for fuel upgrades.
Opinions please.
Thanks, James.
I have been debating about doing heads for awhile now, specifically the TSP stage 2.5 5.3L heads.
I have seen so many H/C car numbers that range from 420 to 470(all M6 cars) and have to say I am alittle discouraged. I know every dyno is different and every car for that matter, but with such a huge difference across the board, I feel like it is a crap shoot on the numbers I can expect.
I would like to hear from some (Patrick G., Predator, Anyone at TSP, etc.) who could give me a reliable expected HP increase by adding these heads.
I know they are supposed to produce around 50rwhp more, but I have seen where they only get 20-30rwhp.
Is mid 440rwhp and 400rwtq a reasonable goal with just the addition of heads? If it's probably only gonna get 30rwhp, then I will more than likely put on nitrous. I need some reassurance before I drop $1100 for heads and another $600 for fuel upgrades.
Opinions please.
Thanks, James.
A 40 rwhp gain is not unreasonable with those heads, but compression is going to be one of the biggest items to swing the power either higher or lower. Typically, the higher the better, but you have to keep an eye on piston to valve clearance when going smaller in chamber size. It pays dividends to run a thinner head gasket...tigher quench and more compression. If you still have adequate P to V, then you can look into milling the heads for some additional compression. TSP is very familiar with the amount of milling you can run with their heads and their cams. Ask them what would be the smallest chamber size you could run with their 5.3L head before running into P to V clearance issues.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
With those heads i gained about 40rwhp.Before adding the heads i was cammed(TR224/112) and put down 348rwhp,ifthe heads would give 40rwhp(great for the price)that would have given me 390rwhp,but wanted to be over 400rwhp in an A4,so i added a ported fast and Ron at Vengeance said it would give over 20rwhp.In the end i ended up at 410rwhp 400ft so far it was still climbing til my driveshaft took adump.Total gains was 62rwhp with those heads and ported fast.Hope thise helps you out.My dyno sheet is posted here"A4 Tr224/112cam TSPst2.5 5.3 heads ported 90/90"look for this post/thread to see the sheet
now that u bring this up i wonder how much if any the stock ls1 heads could be milled while running a .040 gasket.
have u looked at the tsp ls6 2.5's? maybe they would produce better power with the t2-mines likes to be high in the rpms-im shifting at 6800.
have u looked at the tsp ls6 2.5's? maybe they would produce better power with the t2-mines likes to be high in the rpms-im shifting at 6800.
Thread Starter
Joined: Jun 2002
Posts: 669
Likes: 1
From: Amarillo, TX
Thanks Patrick, I think Jason said they could mill a little more off to get close to 11:1, so I guess I need to look into that. Even at 11:1 my DCR is only gonna be around 8.1-8.2 
I've looked at them all and the 5.3L casting have smaller runners to improve velocity and they have higher compression with larger valves. I shift at 6400rpm...my dyno graph is in my cardomain link.
I've looked at them all and the 5.3L casting have smaller runners to improve velocity and they have higher compression with larger valves. I shift at 6400rpm...my dyno graph is in my cardomain link.
Last edited by Dr. Jeckel; Feb 14, 2007 at 03:22 PM.
The heads should pick you up another 40-45 RWHP. They will work great with that cam. You should be able to run a .040" head gasket and tighten the quench up or mill the heads to bump up the compression. We have run this setup on numerous cars with great results! 
Originally Posted by Jon@Texas-Speed
The heads should pick you up another 40-45 RWHP. They will work great with that cam. You should be able to run a .040" head gasket and tighten the quench up or mill the heads to bump up the compression. We have run this setup on numerous cars with great results!
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I would like to get these heads some day too...just waiting to see how my tax return turns out. $1100 is a great deal for those heads based on the normal power gains people have been seeing plus the dual springs they come with. My Comp 918's have around 15K miles on them now so when it's time to throw on some new springs I'll probably just do heads/springs at the same time to make it easy...plus the huge power jump won't hurt either!!
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Originally Posted by Red99TA
I would like to get these heads some day too...just waiting to see how my tax return turns out. $1100 is a great deal for those heads based on the normal power gains people have been seeing plus the dual springs they come with. My Comp 918's have around 15K miles on them now so when it's time to throw on some new springs I'll probably just do heads/springs at the same time to make it easy...plus the huge power jump won't hurt either!!
Originally Posted by john563
buy them you wont be disappointed.For $1100 and i gained over 40rwhp in a Stalled A4 thats a helluva gain/deal
And I definitely want at least 400 RWTQ...I'm at 380 now. 