I saw on a site where they have the advertised HP/Tq and the Gibson and JBA's were 15-20hp and 26tq

the Thorley's which are longer and have there own pipe back to the cats only advertised 15hp and 20tq

Shouldnt it be common sense that the longer header would make more HP and TQ? I mean thats the concept for LS1 cars anyway.

Im trying to decide on a good header for my 98Z71 and I didnt know if its worth spending 500 on longer ones compared to 300-400 on shorties

 

where did you find the thorleys?

<small>[ December 05, 2002, 04:16 PM: Message edited by: RED2K ]</small>

 

The Thorley's are brand new and nobody here has them yet. But take into consideration the powers of advertising. JBA and Gibson may be stating numbers from a TBI truck and/or crank numbers. The Thorleys may be talking RWHP. I know guys with Gibsons that got an amazing 2 rwhp!

Greg

I have contacted Thorley myself to get some more info.

 

http://www.truckperformance.com/ has them for the 98's but im not sure if they are out for the newer model GM's

2hp from a gibson header <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> 300-400 bucks for HP LOL

anyone have any decent gains from the JBA's?

But I just figured since I was doing headers I might as well get long tubes.. Ive found Thorleys coated for 500-600bucks. I like the other guys headers, but there 750+
FAST 4.8, let me know what you find out and thanks for looking into it also!

 

You're gonna get different gains on a vortec 350 than the 5.3's. The shorty headers do nothing for the 5.3's b/c the manifold design already resembles a shorty header. Most go mid/long tube for the 5.3 and get 20+hp/20+tq rear wheel. As far as the vortec 350's, I couldn't say about the shorties. I do know someone that put edelbrocks on and noticed a decent gain.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by red53gmc:
<strong>You're gonna get different gains on a vortec 350 than the 5.3's. The shorty headers do nothing for the 5.3's b/c the manifold design already resembles a shorty header. Most go mid/long tube for the 5.3 and get 20+hp/20+tq rear wheel. As far as the vortec 350's, I couldn't say about the shorties. I do know someone that put edelbrocks on and noticed a decent gain.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">thanks for the info.. and BTW, nice ET's for your mods! Its nice seeing a truck that can kick alotta stangs around!

if it makes any difference im not looking into doing anything internal to my motor. Just a crank pulley, intake, header, and thats about it. I have thought about using my dry TNT kit on the truck someway that i took off the car <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />