How to Add Horsepower to the 2004 GXP
Senior Member
True Car Nut
Joined: Jan 2003
Posts: 3,734
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From: Bloomington-Normal, IL 1997 SE

Originally Posted by Sol
Originally Posted by mikey
rockers on a dohc
in that case, a nice cam would do the trick. but 4 cams would be expensive
cams wouldn't be such a good idea in a gxp. its to heavy, it'll take the torque away. it works in a l67 cause you put in a smaller pully and you have to much torque anyways. chfrab does it because there in sandrails, there so light they dont need all the torque.
highstall torque convertor would help, but......forget this bolt on crap, blow it!
highstall torque convertor would help, but......forget this bolt on crap, blow it!
You may want research the feasibility of using some the go-fast goddies GM is developing for RWD northstars. i believe they are going to bolt-on a supercharger for the STS-V and SRX-V. The STS annoucement at the autoshow also stated that the RWD northstar included forged internals for forced induction.
The heads/cam package from CHRFAB is suppose to boost output to 470 horsepower. I am not sure what this does to the power curve, and it would probably require a custom PCM program to get the most out of it and maybe even to run or idle.
I think a lot of the caddy guys do intake and exhaust, and then go nitrous. There is another member on here (speedguy) who was looking to do a turbo kit.
I believe someone also already mentioned that XMS was working on a supercharger kit.
I think a heads/cam package and a supercharger would be the best combo. This may let us run down the big dawg super sedans - like the 469HP Mercedes E55 AMG!!!
The heads/cam package from CHRFAB is suppose to boost output to 470 horsepower. I am not sure what this does to the power curve, and it would probably require a custom PCM program to get the most out of it and maybe even to run or idle.
I think a lot of the caddy guys do intake and exhaust, and then go nitrous. There is another member on here (speedguy) who was looking to do a turbo kit.
I believe someone also already mentioned that XMS was working on a supercharger kit.
I think a heads/cam package and a supercharger would be the best combo. This may let us run down the big dawg super sedans - like the 469HP Mercedes E55 AMG!!!
If I were Scott I would get a Turbo or a Supercharger. And hell, he has a really nice turbo and a really nice Blowzilla there...why not just unbolt them off the cars they are on and put them on the GXP.
OK, so its not that easy...but I would definately go forced induction.
Shawn
OK, so its not that easy...but I would definately go forced induction.
Shawn
I have owned a number of GTP'* and when we opened up the exhaust the low end was always lacking. I would think the easiest and most affordable way to go would be the PCM. The guys at DHP did a lot of work on the GTP'*. I seem to remember that BadSSEI was a member on the Grand Prix club board, probably still is. I havn't had a chance to dig under the hood to much as i have only had the car for a week or two. Just got back from IRAQ and bought it. I am looking forward to the mods disscussions and all the info here.
no vacation there!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! thanks for your kind words. i think the wife and kids were the happiest to see me home. there is no place like home, there is no place like home! never thought i would be so happy to kiss some dirt as i was a few weeks ago!
It is good to be home. I am sure there are some good north star sites, so if anyone can recommed one or two i would greatly apperciate it.
It is good to be home. I am sure there are some good north star sites, so if anyone can recommed one or two i would greatly apperciate it.


