is about 325 hp way out of the question for a gtp i know its possible i mean anything is pretty much ive seen zzps gtp on you tube but what would u all need to do to the gtp to get it running that

intercooler and small pulley would probably get you close. You talking at the crank or wheels?

Intercooler, small pulley, headers cam and probably a few others I'm forgetting.

Too keep it reliable.

Of course a hundred shot of NOS would be the quick way.

The problem is the trans was never designed to hold up to that much oomph.

so basically 100% exhaust job and intercooler and smaller puller and supports is it?

Pretty much. You don't need 100% exhaust. Stock catback is fine, just replace stock manifolds and downpipe with headers and you're good to go.

This is an old out of date chart, but might give you some ideas, there's many different paths. http://www.clubgp.com/newforum/tm.asp?m=5178946&p=1&tmode=1&smode=1 It looks like you'll need to dump the stock cam to 325+ HP at the wheels.

what is the best exhaust cause if anything id like just all new exhaust to have it out of the way for future mods and i was just wondering what is the best sounding exhaust i have done alot of youtubing and ive noticed 3800s arnt the best sounding engine but there are a few i liked. what im looking for is a little bit louder then stock and i would like it deeper with no rasp or whatever its called so basically a bit musclish but no where near ricey( i dont like the sound or look of fartcans and im sure you guys dont either)

Sorry but the best sounding exhaust on these is either stock or a radical cam. Otherwise your SOL.

Besides while it maybe ugly the stock cat-back isn't all that restrictive and flows plenty for motors in excess of 500hp.

Your better off spending your money on the cat-forward.

I spoke to an exhaust guy about a month ago. He had STRONGLY suggested the magnaflow exhausts for these engines. Otherwise, some kind of header or ported manifold, u-bend delete, high-flow cat, and some nice tips. After that, you're pretty much done.

thanks and i guess i have noticed alot of magnaflow on gps anyone else have any opinions? o and which cai gives thehighest hp gain i would rather have a cai over a fwi and stuff and i know k&n gives like 13.34 or something like that and others that give more tho?

cheers, homie. Glad I could be of help.

They are all about the same. No one has ever done comparison runs between all the options available. I'd put money on it that any CAI that uses a 9" cone will net the same results regardless of the make.

There's just too many variables. You won't go wrong with any of them.

I still say stock exhaust is the best. Sure it'll sound good at idle but once you get into the RPMs they all have that icky nasty rasp sound and the drone in the cabin gets old after a while.

i like stock ijust want it a little bit deeper and a bit louder cause my dad has a 68 chevelle and i love absolutely love the sound of it now i know a gp will never sound like that but i just want a hint of muscle like it and a bit louder and no rasp is tat possible?

Only one I ever heard that sounded anywhere near what your after had a radicle cam in it. Otherwise your chasing the great white buffalo.

wait does the actual exhaust have much to do with it or is it more the cams

more so the cam, but to an extent, both. I know, not much of an answer, and I'm sorry, but that's the nature of these cars.

but isnt the cam in the valve train? or whatever its called

it is. Other components that make a difference in the valvetrain is the rocker arms and springs.

EDIT: I spoke to Comp Cams a while back, and they had told me that it would cost about 800USD for about 35 chp. Cost prohibitive for my application.

Yes the cam is what controls the valve train. It determines when and how much a valve opens and closes. It controls how much air is let in and how much air is let out. The timing of which changes the sound output which is then modified by the exhaust system. If you don't change the cam all you'll change is the idle sound and how loud the rasp gets when you get on the throttle.

T-bat was trying for the sound you covet ask him how many exhaust variations he went through before he found something somewhat exceptable.

I gave up and went back to stock. Haven't regretted it one bit.

but dont you need exhaust mods if your gonna further mod your car?

Exhaust meaning catback or before? You absolutely need a downpipe. It's one of the first mods anyone does to start dropping pullies on the supercharger. Biggest factory restriction. Next would be front exhaust manifold, then probably the factory catback.

I'm at the point I'm running headers into a full 3" custom catback system. Even with all that, I have tons of torque. Of course, my car is anything but stock, but yeah you have to mod exhaust here and there. Also, I started out with Flowmasters, then went to Dynomax mufflers for a sound reduction. I'm pretty content atm, nice mix between rumble and highway cruising volume.

but would it matter if i just off the line skipped the dp and got full exhaust from someone cause if i got magnaflow full exhaust thats straightpiped technically right? oh and my car has a bad lift and on a scale of 1-10 how hard would it be to replace

Straight piped is straight piped. Muffler, and if it's a road vehicle, catalytic convertor isn't straight piped. Also, without other mods, you'll lose low end torque even if you gain high rpm breathing. My car is like this: Headers>catalytic convertor>glasspack>mufflers. 3" from the headers back, but I'm cammed with 3.25" pulley and stuff. I can't go full throttle in first gear pretty much (I also blame tires lol), so it's not like I'm starving for torque.

If you can get your car on jack stands, know what you're doing, and have a decent tool set, I'd say a 5. Mainly cause you're going to have to fight some stubborn, rusty bolts.

Typically aftermarket exhaust systems like Magnaflow etc are only cat backs. And will net no gain to a stock or mildly modified GP. The biggest bang for the buck exhaust wise on these cars are the cat forward.

So please clarify what you mean by "full" exhaust.

I don't know how many times we can tell you putting a cat back on will not get these cars to sound anywhere near a small block V8.

Forget everything you are thinking right now. lol. If you want a nice sound, you need a turbo. Like me, lol.

But I know you won't so I will try to help. If I were to build a supercharged motor again, these would be my only mods and to be honest, it would make equal to or more power and sound better than 80% of people who mod their GP's.

Headers w/ cutout
NIC cam
stock timing chain w/ 90# LSx springs
LS1 throttle body
Home-ported Gen3 (GenV's are still too expensive for me)
3" pulley
homemade FWI
Good tune

This should be your exhaust, All you need, Period.

Headers (comes with a 3" donwpipe) and an electric cutout placed in the lower downpipe. Leave the catback stock aside from some new tips if you want a different look. This is the best setup you can get IMO.

Best performance when cutout open (takes 2 seconds to open/close) and quiet when closed with a nice idle. If you want people to hear it if it's not loud enough, open the cutout.

You'll want a cam to reach 325hp, I would suggest a NIC cam. It's the best idle you're going to find for the 3800 and is the cheapest way to reach your goals.

LS1 and Northstar throttle bodies can be found fairly cheap and are a great upgrade to a s/c build. Port the inlet of the supercharger to match the TB.

Replace the timing chain and put on some 90# yellow LSx springs.

Those mods above with a 3" pulley will be more than enough to make your 325 hp goal and more than enough to eventually break hard parts in your transmission.

im sorry i didnt mean straight piped earlier meant downpiped but would this work to cover my exhaust forever basically with the downpipe added http://www.zzperformance.com/grand_prix/products1.php?id=636&catid=110

Keep in mind if you want 300+ your gonna need headers. Once you get headers that down pipe you bought will have to come out. Since the headers have thier own. So given your goal forgo the down pipe and just get the headers.

Yes you can sell your DP once you get headers but you do sell it at a loss.

well id rather just save up and drop the dp from the equation and just get headers and that exhaust and im sorry but what exactly does the resonator do and when i mean drop the dp i mean just wait for the one with header

Resonator removes the annoying drone from the interior of your car. It keeps your head from buzzing from horrible exhaust vibrations.

Keep the resonator. It's not restrictive and you will be happy you did.

ha i was never gonna get rid of it and ive really been thinking about it and i really just want no rasp thats it how can i accomplish this

Go radical on the build or just buy a SBC powered car.

Turbo. That's the only way.

SBC?
and how are twin charged cars? i know they fetch ALOT of hp but compared to maybe a single turbo

SBC = Small Block Chevy. The engine that makes the sound you so covet.

As for twin charged. The tuning requirements for a turbo and S/C can be a bit of a pain. But does yeild good results now a twin turbo set up and the skies the limit.

Single turbo only will work far better than any twin-charged setup and be much easier to setup and tune.

over a twin charged how?

Turbos will always provide more potential power than a blower or twin charged system because they are not parasitic. It takes engine power to turn a blower, turbos turn due to a byproduct of exhaust gas pressure.

That, coupled with the fact you tune for one source of boost makes the turbo the hands down winner. Why get fancy when simple does it, and does it well?

what is the smallest pulley you can get