GTP 4.8L heads are on!
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GTP 4.8L heads are on! Just started her up tonight and everything looks/sounds good. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Big thanks to Jason for helping with the install! <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
We installed GTP 4.8L heads milled .015 and ARP head studs. I've got pictures and video of all of it here.
Time to get it on the dyno and get back to the track. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Justin
We installed GTP 4.8L heads milled .015 and ARP head studs. I've got pictures and video of all of it here.
Time to get it on the dyno and get back to the track. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Justin
Re: GTP 4.8L heads are on! Sweet brother! <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
Looks like we will have some more competion at the Thunder Shootout Nov.2. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
Keep us updated my friend. <img border="0" alt="[angel]" title="" src="graemlins/gr_angel.gif" />
Looks like we will have some more competion at the Thunder Shootout Nov.2. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
Keep us updated my friend. <img border="0" alt="[angel]" title="" src="graemlins/gr_angel.gif" />
I can shift faster than you.
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From: Baton Rouge, LA
Re: GTP 4.8L heads are on! <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" /> .. No problem on the help Justin. I'm glad we finally got some bad *** heads on your car. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Time to bring it in for some tuning and then bolt the slicks on. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Time to bring it in for some tuning and then bolt the slicks on. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
I can shift faster than you.
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From: Baton Rouge, LA
Re: GTP 4.8L heads are on! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by jmX:
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Jon, this is just a characteristic of Craig's port design. Every set of LS1/5.3l GTPs I have put on the flow bench have done this. GTP LS6 heads do not have this dip until you get to much higher lifts (close to .700). As long as you are not running a large lift cam, you are just fine. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Craig's heads really shine in the low/mid lifts where you are going to spend a vast majority of your time. This, along with his real small ports, makes for an excellent street/strip cylinder head.
Jason
<small>[ September 11, 2002, 10:31 PM: Message edited by: Jason99T/A ]</small>
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Jon, this is just a characteristic of Craig's port design. Every set of LS1/5.3l GTPs I have put on the flow bench have done this. GTP LS6 heads do not have this dip until you get to much higher lifts (close to .700). As long as you are not running a large lift cam, you are just fine. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Craig's heads really shine in the low/mid lifts where you are going to spend a vast majority of your time. This, along with his real small ports, makes for an excellent street/strip cylinder head.
Jason
<small>[ September 11, 2002, 10:31 PM: Message edited by: Jason99T/A ]</small>
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Re: GTP 4.8L heads are on! Badass Justin!! Your car sounds sick <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Re: GTP 4.8L heads are on! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Jason99T/A:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by jmX:
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Jon, this is just a characteristic of Craig's port design. Every set of LS1/5.3l GTPs I have put on the flow bench have done this. GTP LS6 heads do not have this dip until you get to much higher lifts (close to .700). As long as you are not running a large lift cam, you are just fine. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Craig's heads really shine in the low/mid lifts where you are going to spend a vast majority of your time. This, along with his real small ports, makes for an excellent street/strip cylinder head.
Jason</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Is there any way in hell that you are going to give us the intake runner cc's or is that a mystery like all LS1 heads?
I wish we could get info on heads for LS1's like we get info on heads from www.weldtech.com
one day, one day
Bret
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by jmX:
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Jon, this is just a characteristic of Craig's port design. Every set of LS1/5.3l GTPs I have put on the flow bench have done this. GTP LS6 heads do not have this dip until you get to much higher lifts (close to .700). As long as you are not running a large lift cam, you are just fine. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Craig's heads really shine in the low/mid lifts where you are going to spend a vast majority of your time. This, along with his real small ports, makes for an excellent street/strip cylinder head.
Jason</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Is there any way in hell that you are going to give us the intake runner cc's or is that a mystery like all LS1 heads?
I wish we could get info on heads for LS1's like we get info on heads from www.weldtech.com
one day, one day
Bret
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Re: GTP 4.8L heads are on! I am happy to hear you have that monster together Justin.. I cant wait to hear what she now runs at the track.. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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Verdad Gallardo Re: GTP 4.8L heads are on! Oh yeah.. I cant wait to see another reason why I should have went GTP <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<small>[ September 12, 2002, 10:47 AM: Message edited by: VINCE ]</small>
<small>[ September 12, 2002, 10:47 AM: Message edited by: VINCE ]</small>
Re: GTP 4.8L heads are on! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Jsears8:
<strong>We installed GTP 4.8L heads milled .015 and ARP head studs. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Wow, are are the chamber sizes on the heads and what compression level are you running?
<strong>We installed GTP 4.8L heads milled .015 and ARP head studs. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Wow, are are the chamber sizes on the heads and what compression level are you running?
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From: Louisiana
Re: GTP 4.8L heads are on! Thanks guys..
Coach, I will be observing with my video camera on Nov. 2nd. But would love to race on Friday night. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
Verbs, open headers. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Vince, thanks, once I get it re-tuned I will be living at the track on Sundays. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
ls1290, same as the 5.3L heads I believe. 11.1:1 compression ratio.
Justin
Coach, I will be observing with my video camera on Nov. 2nd. But would love to race on Friday night. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
Verbs, open headers. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Vince, thanks, once I get it re-tuned I will be living at the track on Sundays. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
ls1290, same as the 5.3L heads I believe. 11.1:1 compression ratio.
Justin
Staging Lane
Joined: Jan 2002
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From: Baton Rouge, La.
Re: GTP 4.8L heads are on! Hey Justin, I,m glad you got your new heads installed. I,m also glad you got them in the first place because I got your old heads. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> I received your PM and I will let you know how they do on my engine. Jason wants to help me build this engine, do you think he knows what he is doing?LOL <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Re: GTP 4.8L heads are on! Hey Justin , let me know when you want to line it up with me so we can see just how bad you beat mine (just for kicks) <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Your car should be bad **** .
I can shift faster than you.
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From: Baton Rouge, LA
Re: GTP 4.8L heads are on! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by joghotrod:
<strong>Jason wants to help me build this engine, do you think he knows what he is doing?LOL <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">LOL.. I'll remember this next time you need some help. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
Looks like I'll be building a motor very similar to yours, except I'll be using JE forged pistons. I'll get plenty of practice on that one before we do yours. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong>Jason wants to help me build this engine, do you think he knows what he is doing?LOL <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">LOL.. I'll remember this next time you need some help. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
Looks like I'll be building a motor very similar to yours, except I'll be using JE forged pistons. I'll get plenty of practice on that one before we do yours. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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From: Louisiana
Re: GTP 4.8L heads are on! joghotrod, no prob bob. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> LOL I don't think Jason has ever worked on a car before? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Haha, just kidding, Jason you da man! <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />
Chad, anytime, bring it. <img border="0" alt="[devil]" title="" src="graemlins/gr_devil.gif" /> I'm going to be at the show infront of work for a little while with the car tonight.
Later,
Justin
Chad, anytime, bring it. <img border="0" alt="[devil]" title="" src="graemlins/gr_devil.gif" /> I'm going to be at the show infront of work for a little while with the car tonight.
Later,
Justin
Re: GTP 4.8L heads are on! Hey Justin, I had to work but we can do it any time . I sure dont expect to win but I AINT SKEERED. <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" /> <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />
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From: new england
Re: GTP 4.8L heads are on! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by jmX:
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">There are two schools of thought on this condition, either airflow thru port comes seperated from one side wall of port making flow drop after peak , or at lift just above peak there is a flow collision of separate areas in port as they enter cylinder and slightly cancel each other out causing dip in flow.This is a pronounced problem when hi swirl design and minimum port size are factors of head design. This would explain why LS6 head has a higher lift point where flow dips, because it is a larger port than LS1 heads, and doesnt have same swirl characteristics either. I will test over this offseason to determine exactly what goes on in port at the flow where dip occurs.
<strong>Interesting that both your heads and my heads have the same fall off right after peak on the intake, then it picks back up again. Wonder why?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">There are two schools of thought on this condition, either airflow thru port comes seperated from one side wall of port making flow drop after peak , or at lift just above peak there is a flow collision of separate areas in port as they enter cylinder and slightly cancel each other out causing dip in flow.This is a pronounced problem when hi swirl design and minimum port size are factors of head design. This would explain why LS6 head has a higher lift point where flow dips, because it is a larger port than LS1 heads, and doesnt have same swirl characteristics either. I will test over this offseason to determine exactly what goes on in port at the flow where dip occurs.