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Need help with modding my GTP!

B

Btownmills

New member
I recently purchased a GTP and want to get right down to business and get some modding done to it. I'm new here, and have searched around, but don't know what route to take. There seems to be a lot of possibilities.

I am shooting for only performance mods.

98 GTP w/ 126k on it.

My thoughts:
Full exhaust system
New headers
Cold air intake
New supercharger pulley

I'm not sure what else can be done and what the price range would be. I'm looking to spend around 2k. Also, it would be nice to get some good brand names. I'm not yet familiar with reputable GP brands.

I am located in Wisconsin if anybody would have parts or anything for sale also! Thanks a lot guys!
 


you also should get a tune with those mods too and 2k is way more then you need for them mods IMO, 2k can get you alot more mods. make your own intake, headers from ebay, pulleys are not to much either, and you really don't need a full exhaust, i don't think they sound that great with them anyway
 
Read some more.

Skip the full exahust, you'll gain nothing.
SSAC headers are good, 225 shipped, add a few bucks for better clamps and rtv sealant.
Make your own intake, buying one is a waste of money. AEM is currenty selling these bomb air filters for 20ish shippied, search for that thread about it.

Pulley size is up to you, most will go 3.4 pulley and add a canned tune from Intense or Overkill.

Dont forget about gauges, you'll want to monitor things, like boost/vac and a scangauge to read KR and alot of other things important when modding.

Everything I said is well under 800 bucks.
 
gtpeddie said:
http://www.grandprixforums.net/safely-modding-your-3800-powered-car-17482.html
Click to expand...

KeithGTP03 said:
Start here. Blue included pricing and all.
http://www.grandprixforums.net/safely-modding-your-3800-powered-car-17482.html
Click to expand...

I actually took a look through that thread earlier. I'm not exactly sure what all of it is even. I don't know how to go about buying it all, brands etc., and installation.

Fivefingerdeathpunch said:
Read some more.

Skip the full exahust, you'll gain nothing.
SSAC headers are good, 225 shipped, add a few bucks for better clamps and rtv sealant.
Make your own intake, buying one is a waste of money. AEM is currenty selling these bomb air filters for 20ish shippied, search for that thread about it.

Pulley size is up to you, most will go 3.4 pulley and add a canned tune from Intense or Overkill.

Dont forget about gauges, you'll want to monitor things, like boost/vac and a scangauge to read KR and alot of other things important when modding.

Everything I said is well under 800 bucks.
Click to expand...

I saw 3.4" pulley as being good but read I'd want to finish supporting mods for it first. Such as intake, exhaust etc. How easy are gauges to install?
 


the most important gauge IMO is the aeroforce interceptor scan gauge and that seems pretty easy to install i don't have one yet but it looked easy to install check the how to thread, it just plugs into your OBD2 port and you might have to run a power wire to it
 
gtpeddie said:
the most important gauge IMO is the aeroforce interceptor scan gauge and that seems pretty easy to install i don't have one yet but it looked easy to install check the how to thread, it just plugs into your OBD2 port and you might have to run a power wire to it
Click to expand...

I'm brand new to the idea of gauges, and basically modding in general. Would be so nice if I could find a good GP mechanic in SE Wisconsin that could help me out at a decent cost. Might take a look around the forum and see if anybody would help me out. Worth a shot!
 
yea you should CAI/HAI witch ever you wanna do first then headers, scan gauge, etc.. do the pulley after you have all your flow mods
 
Installation wise, you can find how to install just about anything here. (You may want to type your install question into google and it will show you a link to a thread here.) As for gauges, if you can wire a stereo, you can wire gauges. There are also plenty of instructions here for those too. Google search "how to install gauges on a Grand Prix" and I bet the first few will bring you back to threads on this site.
 
KeithGTP03 said:
Installation wise, you can find how to install just about anything here. (You may want to type your install question into google and it will show you a link to a thread here.) As for gauges, if you can wire a stereo, you can wire gauges. There are also plenty of instructions here for those too. Google search "how to install gauges on a Grand Prix" and I bet the first few will bring you back to threads on this site.
Click to expand...

I just took a quick look and gauges definitely could be done myself. I just don't know what brand names for mods to get. Or where to order from for the best price. I took a look around a figured a SLP full exhaust system, k&n cai, intense pulley, but have no clue where to get headers or how much they would cost.
 


ebay for headers, you dont need crazy expensive ones unless your doing heavy mods. make your own intake or K&N if you want its up to you. and im telling you now you might not want a full exhaust system these cars dont sound great with them
 

this is my exhaust and i have stock mufflers this is all you need you will have a drone with mostly any other aftermarket exhaust system even mine sounds a tad bit raspy
 

This is mine with the entire exhaust done, and kept the stock mufflers. 3" down pipe, High flow cat and 3" piping back to the Y. And wasting money on brand name is up to you. You will notice absolutely no performance difference between a K&N system and a Home Depot system. You're wallet will notice a difference, though.
 
For 2K I wouldn't even consider staying S/C because used turbo kits can be had for around that price. Regardless I wouldn't even start throwing performance mods at a 14 year old car. I would fix all the stuff that is currently wrong like leaks and such and then I would move on to brakes and suspension. What's good about a modified car if you cant stop the power or put it down to the ground?
 


It isn't about what brands...it's about learning the platform...the do's and do nots...and not getting hosed by spending $300~ on an intake when a conf ilter for forty bucks slapped on the throttle body works better.

Also...

Cam or nothing.

Because, nothing sounds as good if you keep the blower.

Ala, catless headers, full 3", big glasspack, bullet race muffler before the "Y"...into 4" G8 GXP tips.

GTP Big Cam Idle/Rev - YouTube

Or...hell just dump it

Big Cam GTP Idle & Rev - YouTube
 
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