Thread: A few questions about a GXP

you are going to have a lot more performance options with a GTP because the GXP market is very lacking. sure, they sound great with an intake and an exahust, but beyond that it's slim pickins.

how much money do you have to spend. as a gxp owner i hate to say that if you are looking for a car with alot of mod options go with a gtp instead. right out of the box the gxp is awesome and runs with alot of other cars out there. if you have the money a turbo'd gxp is the best thing you can have in the grand prix range. but thats just my opinion. i love my gxp though. im 5'8" and my head is about 3 inches from the headliner, but the seat has alot of adjustment.

You need to go drive one to see if it fits you well.

actually the only company that makes a bolt on turbo setup sells it for 5500. gas milage actually improves slightly if you can manage to keep your foot out of it. but i wouldnt imagine being able to. the gxp uses a ls4 motor. alot of ls1/2/6 parts will fit with modification but it will cost you. a few guys on the gmls4.com forum are looking at 400 crank hp with a ton of bolt on parts. only one brand of headers is available for a pretty penny. the trans will **** the bed after a while with a large amount of power but it is easily upgradable, again for a price. a well sorted out 500hp 11 sec gxp with a stout trans will cost you around 9g's after the cost of the car.

I'm 6'3 and of wide girth.. My 98 2dr is sooo much bigger on the inside than my dads 06 4dr. The 04+ are a squeeze for me. Less headroom also

Just my .02!

Originally Posted by f3racer

actually the only company that makes a bolt on turbo setup sells it for 5500. gas milage actually improves slightly if you can manage to keep your foot out of it. but i wouldnt imagine being able to. the gxp uses a ls4 motor. alot of ls1/2/6 parts will fit with modification but it will cost you. a few guys on the gmls4.com forum are looking at 400 crank hp with a ton of bolt on parts. only one brand of headers is available for a pretty penny. the trans will **** the bed after a while with a large amount of power but it is easily upgradable, again for a price. a well sorted out 500hp 11 sec gxp with a stout trans will cost you around 9g's after the cost of the car.

haha, I guess I'm not going to get a turbo then. I don't want to put that much into the car.

So... what do you think I can to do one for a couple thousand? Would it even be worth it for the gains I would get?

For a couple grand?

I'd get a built transmission...that way if you ever want to mod down the road and you have the funds...the weak link has been eliminated.

Originally Posted by bluegtp91

For a couple grand?

I'd get a built transmission...that way if you ever want to mod down the road and you have the funds...the weak link has been eliminated.

agreed. get with these guys
Triple Edge Performance - Home Page

go with a built trans and 3.69 gearing and the car will be a whole new monster.

I have owned both a gtp and i own a gxp currently, and honestly i can say i like the gxp more. i do miss the whine of the s/c, but it was quickly forgotten with the sound of an LS4. the only downfall is the transmission, and like the gentlemen before me have said, build it up first. some stock LS4's have have transmission problems before 100,000 miles.

pretty sure the catback wont net you any hp gains, it will just sound cool. go with a downpipe if you want to free up your exhaust. and well headers of course.

Originally Posted by Walleyealx

ok, definiltey sounds like that would be an option.

I've also been digging a bit more and found a few parts that sound interesting.

1. Magnaflow catback exhaust

2. K&N Aircharger

3. Vector performance tune ecm/tcm tune.

It looks like if I got all of those it would improve HP close by as much as 40. How true are the numbers that they usually publish on these?

Advanced auto parts has 20% off online orders and free shipping for until the end of november, so the exhaust and aircharger would be quite a bit cheaper than usual.

Anyone have any experience with these specific mods? Any other suggestions?

1. maybe 5hp maybe
2. same
3. will net you around 15 combine with the other mods. a dyno tune is the best way to go or http://www.diablewtune.com/ he is the best in the bizz when it come to the ls4. he will free up alot.

headers will net you good gains but there is only 1 company that makes them and they are almost a grand. HEADERS at Doug Thorley Headers dougthorleyheaders.com

this is what i did. for about 50 bucks total i cut out the cat, and the mufflers. i left the resonator in place. it gave me great sound and freed up a little power. then i had the o2 sensor tuned out.
stock sound
boostnsrt's Channel - YouTube

just mufflers removed
boostnsrt's Channel - YouTube

mufflers and cat removed
boostnsrt's Channel - YouTube
will @overkill does a cheap tune and right now is the only person out there that tunes the trans as well. i have this tune. it doesnt produce much power, but does improve the drivability, and the trans tune by itself is worth the money you pay.

Originally Posted by Deimos

Oh sure but you wont answer my questions

what did i miss? maybe i missed your thread.