Curious on this too! mine are being installed today!
GM Performance Heads
Team Owner
Joined: May 2003
Posts: 23,480
Likes: 9
From: East Meadow NY
St. Jude Donor '12
IIRC, Those are on my car. They will not flow as well as the AFR's, but they are less expensive.
Last edited by chaase; Jun 23, 2008 at 04:55 PM.
Drifting
Joined: Feb 2007
Posts: 1,446
Likes: 0
From: Cranford NJ
As stated above, they won't flow as well as a set of AFRs, but are cheaper. There are many options for cylinder heads. Give us a call if you want a hand selecting what will work best for you.
Max
908.317.4496
Max
908.317.4496
Racer
Joined: May 2006
Posts: 431
Likes: 0
From: Houston TX
Drifting
Joined: Jun 2006
Posts: 1,702
Likes: 1
Personally I can not see investing in a new set of heads that might net me a additional 10/10 increase overall. However,if I was swapping out my stock heads then I would have to consider (purchase) the best set of heads for my application.
I would like to see a independent test conducted on all possible combos (NA,Nitrous,and FI) using the various manufactures heads that are available to us LS guys. But being realistic that will never happen...you will just have to go with the bias data and hype available and then make your own decision.
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Racer
Joined: May 2006
Posts: 431
Likes: 0
From: Houston TX
I have been running the GMPP cnc heads for the past five years. The part # back then was 12480176. The heads flow a little over 300 cfm at 600 lift with 60cc chambers. I realize that there are a lot of after market heads today that claim superior flow numbers to the GMPP cnc heads..which may be very well true. The heads perform well and you will see a nice increase in power when their matched with a good cam (combo). The present cost for a set of these heads is approximately $2200.00...not exactly what I would call cheap!
Personally I can not see investing in a new set of heads that might net me a additional 10/10 increase overall. However,if I was swapping out my stock heads then I would have to consider (purchase) the best set of heads for my application.
I would like to see a independent test conducted on all possible combos (NA,Nitrous,and FI) using the various manufactures heads that are available to us LS guys. But being realistic that will never happen...you will just have to go with the bias data and hype available and then make your own decision.
Personally I can not see investing in a new set of heads that might net me a additional 10/10 increase overall. However,if I was swapping out my stock heads then I would have to consider (purchase) the best set of heads for my application.
I would like to see a independent test conducted on all possible combos (NA,Nitrous,and FI) using the various manufactures heads that are available to us LS guys. But being realistic that will never happen...you will just have to go with the bias data and hype available and then make your own decision.
I have a buddy that went from Ported LS6 heads to Trickflow heads and he gained 10rwhp.
Thread Starter
Advanced
Joined: Sep 2004
Posts: 50
Likes: 0
From: Salem Oregon
I decided to go with the AFRs they were about the same cost as the GMPP, but have smaller cc intake runners. I already have MTI LS1 R2 heads with large intake runners
A Thunder racing cheater cam, LGM long tubes. I need more lower midrange power to 6000rpm. more than top end. I use the car for HPDE track days on a road race corse.
Thank you the for input
A Thunder racing cheater cam, LGM long tubes. I need more lower midrange power to 6000rpm. more than top end. I use the car for HPDE track days on a road race corse.
Thank you the for input
Le Mans Master
Joined: Jun 2006
Posts: 6,979
Likes: 31
From: Wichita KS
Yea they may be good for 10-15 rwhp up TOP but the midrange power will blow the LS6 heads out of the water, the cfm at .200-.500 (where it matters) is huge on the Trick Flows
Drifting
Joined: Jun 2006
Posts: 1,702
Likes: 1
Saying that the Trick Flow heads will blow this GMPP set of heads out of the water is somewhat of an over statement. I am not saying that this set of GMPP heads are the best that money can buy....just that they produce good HP/TQ with the right combo.
Racer
Joined: May 2006
Posts: 431
Likes: 0
From: Houston TX
They don't blow the ported LS6 heads out of the water, but they are significantly better in the low range (15-20 lbs-ft tq) and the TFS does allow you to run a larger cam without having to worry about flycutting as compared to the LS6 heads.
Last edited by 11sec_C5Z51; Jun 26, 2008 at 12:57 PM.
Drifting
Joined: Jun 2006
Posts: 1,702
Likes: 1
doubt if its anywhere near 15rwhp. Comparing his TFS to his Ported LS6 heads, rwhp was comparable in the midrange, the biggest difference was the TQ in the midrange. He gained 1 mph in the 1/4.
They don't blow the ported LS6 heads out of the water, but they are significantly better in the low range (15-20 lbs-ft tq) and the TFS does allow you to run a larger cam without having to worry about flycutting as compared to the LS6 heads.
They don't blow the ported LS6 heads out of the water, but they are significantly better in the low range (15-20 lbs-ft tq) and the TFS does allow you to run a larger cam without having to worry about flycutting as compared to the LS6 heads.
Last edited by 98vettedave; Jun 27, 2008 at 03:00 AM. Reason: mistake
