Basic Mod Preference

**xawahl** · 01-07-2009

I know this has probably been posted up before. I just got my 98 GTP a few weeks ago, and now doing the prep for a little more power and to kill KR. What is the thoughts on this list and what else would i need to be done to make a reliable daily driver with a little more power than stock

Autolite 104
180* T-stat
New water pump
gutted cat
Ubend delete
3.4 pulley
4" intake
ZZP PCM

This is what it will have when im finished over the weekend, is there anything im missing on this to kill KR and make it run smooth.

**Bio248** · 01-07-2009

get a downpipe or youre looking to have a significant amount of knock with that 3.4. also, you may want to look into a PLOG as well.

**blowfishRus6** · 01-07-2009

stay away from zzp pcm. alot of people have problems with those.

my recemendation is overkill

**TheOtherNick** · 01-07-2009

Yeah get an overkill pcm and bump the pulley up to a 3.5. Also get a down pipe instead of the ubend. You should be set. I have a 3.5 on my car now and there is a huge difference over stock.

**xawahl** · 01-07-2009

pcm is already on it. thinking about doing the complete header with DP, with the 3.4 do i need full header or just DP. 3.4 is the smallest ill be getting

TDCRacing · 01-07-2009

Yeah get a downpipe over a u-bend deleate. And If you're looking for a Fender Well Intake Let me know as I sell them. And you even get A discount for being a member on the forums.

NEW Product TDCRacing FWI - Page 8 - Pontiac Grand Prix Forums : Grandprix

**Bio248** · 01-07-2009

if the smallest pulley youll ever be getting is a 3.4 then done waste money on headers. they arent worth having at that point.

id run a 3" downpipe, a power log, intake, 180* thermostat, colder plugs, and the 3.4 pulley. that should keep you from knocking a lot and provide a long lasting fun setup.

**98SilvermistGTP** · 01-07-2009

Add an Autotap or some kind of scanner to that list.....
Yeah, the downpipe is what you need, just getting rid of the Ubend is only part of the problem with the stock downpipe, it is restrictive at the opening, an aftermarket one is a full three inches. Why the water pump? Is yours going bad or something?

**TheOtherNick** · 01-08-2009

If a 3.4 is the smallest you are getting you will be fine with a dp and plog.

**xawahl** · 01-08-2009

with the water pump, the gasket is leaking, and its loosing coolant...not a lot, enough to go ahead an replace it all though

**Reptile** · 01-08-2009

Also, shameless plug for me here....but doing some blower work wouldn't be a bad idea sometime soon. It'll lower the outlet temp of the air charge and give you a little more of a whine.

PM me if you're interested.

**98SilvermistGTP** · 01-09-2009

If you need a heads up on the water pump, let me know, I just changed mine a couple months ago....

**VinnieGTP** · 01-10-2009

I'm suprised at the responces in this thread. It has only been suggested once that he buy a scanner and no one told him NOT TO DROP PULLEY SIZES UNTIL HE'S SURE HE DOESN'T HAVE KR ALREADY!

Cars stock correct? Here's what you'll want to do:

Plugs -Autolite 605s, 104s are too cold for a stock car.
T-Stat - 180 for winter and 160 for summer with a 1998
PCM - They're all pretty much the same and you'll be doing a custom dynotune in the future anyway if this is a serious build so get what you want.
Down Pipe - 3" with no cat if you can get away with it in your area.
Intake - Pick one, they're all the same at your level of mode but the TDC one is really nice for the $$$ but at you're level I would just gut the stock airbox of the internal baffeling and call it a day for free.
Powerlog, PEMs or headers - Not at this point IMO
Electronics Cleaner and Carb cleaner

If you can remove your cat then you can remove your EGR. If you remove your EGR the first thing you'll want to do is clean yout TB from all the gunk over 11 years for better throttle responce. Pick up a TB gasket and pull the TB. Remove the MAF from the TB. Get a toothbrush and a can of carb cleaner and get to scrubbing the TB. After that, spray the MAF sensor with the electronics cleaner and enjoy the new found throttle responce.

**VinnieGTP** · 01-10-2009

Oh, and why are you changing your water pump?

**xawahl** · 01-11-2009

changing water pump because it is spraying coolant out through the gasket, and i have to take it off anyway so im going to put a new pump on there. Its cheap

**xawahl** · 01-13-2009

So ive finally got everything on it...3.5 pulley will be here tomorrow, decided to go a little bigger at first until i can get the power log. downpipe is getting put on as we speak. So heres the list of what was on it when i got it.

It had zzp pcm, 4" intake, gutted cat. Those were the only things done to it when i got it back right before christmas.

This is what I just completed,
180 tstat, autolite104's, new water pump, new belt tensioner's, idler arm pulley, new Alt belt, gator belt for supercharger, have both a 3.5 pulley and 3.4 pulley. 3" dp is being put on right now. will pick it up tonight. Which pulley should go on at this stage, 3.5 or 3.4? Im thinking 3.5 until powerlog can be ordered and get here.

Going up to detroit this weekend for the auto show and driving the gtp. Should i notice a huge drop in gas mileage or just a little?

**Bio248** · 01-13-2009

a 3.5 is safer, but if youre planning on a powerlog right away i would wait on the pulley until you get the powerlog and install them at the same time. if that is the case then get a 3.4.

youre going to notice a huge decrease in mileage because your foot will be on the pedal all the time. otherwise nothing significant.