Thread: Mods for my 98 GTP

I already have a quality tune from Intense, a cold air intake that I made and colder iridium spark plugs.

Originally Posted by 2FASTGTP

But still, think about it. You can get a ZZP downpipe for 150 if you send your old cat in and get $50 back. Install yourself, that saves you $700 to do other stuff to your car! A quality tune, CAI, spark plugs, anything! If your set on headers, go for it

Originally Posted by ngj123

I just don't understand what a downpipe has to do with anything except for it being a little less restrictive. I mean headers should be way better than just throwing on a downpipe.

Headers: probably 3.4" pulley

Downpipe: probably 3.5" pulley

All depends on your situation but it boils down to, is the extra gain from headers worth an additional $700?

8 pages this cannot be a serious thread............

Originally Posted by 98GrandPrixIraqVet

8 pages this cannot be a serious thread............

It's veered of topic a little bit haha

Originally Posted by Grimsin

this thread is lols, headers is way more flow then just a downpipe, the front manifold is very restrictive, the rear one not so much. but if your only mildly modding then downpipe is the way to go.

ngj123: are you paying $850 for just the install? you still have to buy their headers? cause if so thats ridicolouse...

So would a PLOG, u bend delete, straight 3" pipe and a glasspack for sound be good? Screw the downpipe And headers, that basically is a $400 setup with welding from exhaust shop on the glasspack and everything

Originally Posted by REDCOMPG

Straight pipe sounds like ass. Why not just stick with a 3" downpipe (will also get rid of the ubend) and keep everything else stock. Hell you can just weld on new mufflers if you want a different tone.

Ok, the straight pipe was recommended by someone so I brought it up. But we'll see what happens

Originally Posted by REDCOMPG

Go to YouTube. Straight pipes on our cars sound like ass. Stock mufflers are fine.

Alright then....I'll talk to my buddy and see if he wants to attempt headers or not

Yes it was, so what can I do to correctly tune this since it is obvious I have no clue what I am doing?

Originally Posted by REDCOMPG

Guessing this is a mail order tune? Hate to break it to you but a mail order tune can only do so much. A in car tune can adjust the tune to your car not just some generic **** that some guy put together because it worked on another car.

Originally Posted by 2FASTGTP

So would a PLOG, u bend delete, straight 3" pipe and a glasspack for sound be good? Screw the downpipe And headers, that basically is a $400 setup with welding from exhaust shop on the glasspack and everything

Don't need to weld the headers but you want band clamps. But you also have to take in account sd headers crossover will need adjustment,you will need to bash in the firewall for rear 02.
But if you just want sound just change the mufflers .. but nothing sounds better the headers. I'll post a link of my exhaust with 2.5" downpipe. Then another vid of with headers if ya want

Originally Posted by Grimsin

Don't need to weld the headers but you want band clamps. But you also have to take in account sd headers crossover will need adjustment,you will need to bash in the firewall for rear 02.
But if you just want sound just change the mufflers .. but nothing sounds better the headers. I'll post a link of my exhaust with 2.5" downpipe. Then another vid of with headers if ya want

Links would be perfect man! What do you mean by the crossover will need adjusted? What will that require?

Not much we attached the crossover to the front header then forced it on the rear header, wasnt extremely hard but wasny a direct fit either.
I'll get vids later. Watching walking dead atm

Originally Posted by Grimsin

Not much we attached the crossover to the front header then forced it on the rear header, wasnt extremely hard but wasny a direct fit either.
I'll get vids later. Watching walking dead atm

Sounds good man! I need to get a floor jack before any install. There's an auction tommorow with one and my dad is gonna try and get it

Yes but most are across state, seems most people who deal with this platform live in Grand Rapids or Kalamazoo area.

Originally Posted by REDCOMPG

I have some local retune the car for you. Meaning sitting in the car with you while your driving recording data and adjusting the tune accordingly. Your in Michigan...that's Grand Prix central surely you can find a tuner.