AMS SOM TA in GMHTP- yep, thats right!
08-16-2002, 02:25 AM
#1
AMS SOM TA in GMHTP- yep, thats right! I just received the latest issue of GMHTP. On the cover it has a 2002 Sunset Metallic Orange Trans Am built by Arlington Motorsports. It says it is putting down 428rwhp and 410 rwtq with ported GM Vortec 4800 heads (LR4) and a custom grind 226/226 .590/.590 112 LSA cam. It also has Hooker LT’s and true-duals.
My question is about the heads. These are the same heads out of GM full-sized trucks and SUV’s.. ‘slightly ported.’ They said they used these heads because it bumps the compression up a little bit.
I was considering going with locally P&P heads for the sum of only $400. But everyone is telling me that I should just do it right and go with Stage 2 or S3 heads from a known performance shop. What I’m wondering is what’s the difference between this locals heads and the ones from a shop? People are saying that the P&P job is only good for 15rwhp but the S2 or S3’s are good for 35-40 or more! Why??? I’m going to go with a cam from TR and will be getting all of the upgraded goodies that go with the heads (titanium retainers, comp springs, chromemoly pushrods, etc..) Will this set-up be a good motor combination or is there something I’m missing?
My goal is 425 RWHP (I want to claim 500 flywheel hp.) Is my goal feasible with this combo?
TR 224/224 or 227/227 with a 112 LSA either way.
Locally P&P heads with upgraded parts from TR.
LS6 intake
Hooker LT's or MAC's (I need clearance.)
Will I need to upgrade my fuel system with an inline pump and/or bigger injectors? Someone PLEASE explain. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
My question is about the heads. These are the same heads out of GM full-sized trucks and SUV’s.. ‘slightly ported.’ They said they used these heads because it bumps the compression up a little bit.
I was considering going with locally P&P heads for the sum of only $400. But everyone is telling me that I should just do it right and go with Stage 2 or S3 heads from a known performance shop. What I’m wondering is what’s the difference between this locals heads and the ones from a shop? People are saying that the P&P job is only good for 15rwhp but the S2 or S3’s are good for 35-40 or more! Why??? I’m going to go with a cam from TR and will be getting all of the upgraded goodies that go with the heads (titanium retainers, comp springs, chromemoly pushrods, etc..) Will this set-up be a good motor combination or is there something I’m missing?
My goal is 425 RWHP (I want to claim 500 flywheel hp.) Is my goal feasible with this combo?
TR 224/224 or 227/227 with a 112 LSA either way.
Locally P&P heads with upgraded parts from TR.
LS6 intake
Hooker LT's or MAC's (I need clearance.)
Will I need to upgrade my fuel system with an inline pump and/or bigger injectors? Someone PLEASE explain. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
08-16-2002, 08:08 AM
#2
TECH Junkie
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Re: AMS SOM TA in GMHTP- yep, thats right! You have to use a little caution when having someone local do a set of LS1 heads, as the average cylinder head guy probably isn't too familiar with LS1 heads, and can possibly loose power by messing with them. Most of the basic porting/polishing tricks still work with these heads, but when you start just hogging the ports out, you will run into problems.
If you don't mind the extra money, one of the trusted vendors on here would be your safest bet. You'll get quality work from most any of the big names (ARE, MTI, GTP, MMS, etc) but you probably will pay a little more than you would locally. However, you're getting much more than a quick "touch-up" port job though. Most shops heads come with better quality, higher flowing valves, beefier valvesprings, etc.
The truck heads you mentioned are a popular choice for those looking for a bump in compression ratio. I have 4.8L truck heads on my car.
Before deciding on anything, pick what you want to primarily use the car for. Street racing, drag racing, daily driver? That will have a huge impact on what parts you should choose when it comes time to start.
Lastly, keep asking questions here. There is an immense wealth of technical knowledge on this board.
If you don't mind the extra money, one of the trusted vendors on here would be your safest bet. You'll get quality work from most any of the big names (ARE, MTI, GTP, MMS, etc) but you probably will pay a little more than you would locally. However, you're getting much more than a quick "touch-up" port job though. Most shops heads come with better quality, higher flowing valves, beefier valvesprings, etc.
The truck heads you mentioned are a popular choice for those looking for a bump in compression ratio. I have 4.8L truck heads on my car.
Before deciding on anything, pick what you want to primarily use the car for. Street racing, drag racing, daily driver? That will have a huge impact on what parts you should choose when it comes time to start.
Lastly, keep asking questions here. There is an immense wealth of technical knowledge on this board.
08-16-2002, 08:29 AM
#3
SSU Moderator
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Re: AMS SOM TA in GMHTP- yep, thats right! somehow i doubt theyre "slightly ported"
AMS uses GTP as far as I know, and they are likely GTP S2 heads using 4.8's as a core (same as 5.3's).
Im sure Chris tuned it with Edit as well.
Just spend the money. You get what you pay for.
AMS uses GTP as far as I know, and they are likely GTP S2 heads using 4.8's as a core (same as 5.3's).
Im sure Chris tuned it with Edit as well.
Just spend the money. You get what you pay for.
08-16-2002, 10:58 AM
#4
Re: AMS SOM TA in GMHTP- yep, thats right! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by SStolen:
<strong>
Will I need to upgrade my fuel system with an inline pump and/or bigger injectors? Someone PLEASE explain. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The rest of the stuff looks like you already have your answer. You get what you pay for.
Anyhoo, regarding your injectors and fuel pump.
The stock injectors will do you just fine most of the time, but some of us H/C'ers are running into problems in the upper rpm.
The stock injectors in my opinion don't have enough *** to deliver the necessary fuel in the alotted pulse-width time at the higher rpms.
I am currently running a Stage II ARE H/C with some goodies, and I am running into this problem. I spin the motor just a little north of 6800, and my stock injectors are all but tapped out past 6200. I will be getting some 30# (pintle type) to alleviate this problem.
Many claim to not have this problem though.... (or they don't know about it <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> )
<strong>
Will I need to upgrade my fuel system with an inline pump and/or bigger injectors? Someone PLEASE explain. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The rest of the stuff looks like you already have your answer. You get what you pay for.
Anyhoo, regarding your injectors and fuel pump.
The stock injectors will do you just fine most of the time, but some of us H/C'ers are running into problems in the upper rpm.
The stock injectors in my opinion don't have enough *** to deliver the necessary fuel in the alotted pulse-width time at the higher rpms.
I am currently running a Stage II ARE H/C with some goodies, and I am running into this problem. I spin the motor just a little north of 6800, and my stock injectors are all but tapped out past 6200. I will be getting some 30# (pintle type) to alleviate this problem.
Many claim to not have this problem though.... (or they don't know about it <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> )
08-16-2002, 04:00 PM
#6
Launching!
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Re: AMS SOM TA in GMHTP- yep, thats right! Corys SOM car has 4.8 heads, that where ported inhouse. They are basicly cleaned up, with a good valvejob. With GTP's, I would hope the dyno numbers would be better than 428 <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Chris
Chris