New gt prix owner

[prixgt01]

about to buy buy a 01 gt 3.8 with 99k on the clock. question i have for you is what to look for when buying one, engine and tranny wise? Also it will be my dd so good gas mileage is needed but want some mods. what the typical mods people do and is the engine i have a l26 or l36? not sure what thaty means and what the hp rating? thanks for the help in advance.

[Madness]

You will want to try and find out if the upper and lower intake manifold gaskets have been replaced. GM's dexcool has been know to destroy them and let coolant into the oil.

[xringshooter7]

You have an L36, and with all the mods, you will probably be making stock GTP numbers...i would suggest a top swap if you want to make a lot of power. Yeah, def check the LIM gaskets.

[prixgt01]

Great thanks for the fast response, do i swap out the resonator, with a straight through muffler? something with muscle sound not a ricer fart sound. magnaflow,flowmaster, slp loud mouth? And i know a cold air intake anything else to kepp good gas mileage youd suggest and what years can i interchange parts with, whats the gen for this grand prix? And a top swap involes what. thanks agian

[Fivefingerdeathpunch]

HP for a GT is about 200 HP at the crank, so to the wheels its going to be a little less.

Gas Mileage for a GT on the freeway, you should get about 30-33( maybe more) City- around 20 mpgs.

For the air intake just go cheap and make your own or just go on ebay and look up AIR INTAKE FOR GRAND PRIX. It just a pipe with a filter and works great and you should get better milage with it.
Heres a link: Air Intake Pontiac Grand Prix SE GT GTP 1998 1999 2000 : eBay Motors (item 350216994722 end time May-18-10 20:27:24 PDT)

As for exhaust the stock catback is fine. Its just the u-bend that is restrictive. For mufflers it your choice, I dont have a preference.

[prixgt01]

Is there a fender mounted intake for this car, would better pullin cold air then engine heat right? and where is the u bend at exactly?And if you take resonator out with no muffler will it jack the emissions? So thats why i was wonderin what muffler to replace it with. And as stated above whats involed with a top end swap? and what type of numbers to expect or problems? thanks

[Fivefingerdeathpunch]

Colder air will give you more power but can decrease gas mileage. Hot air will give you better mileage but a little less HP. I am not genius about the reason why its that way but its true. Maybe someone else can give you the exact reason why.

The u-bend is right behind the cat i think. There will be a sensor sticking out the top of it.

If you have no resonator the car will sound very raspy, which will sound like crap. If you want a little more sound replace it with a glasspack. And I wouldnt go the no mufflers route. Just put some flowmaster, magnaflow or something like that. Check out youtube and see what you think. But its not gunna sound that good on there, its better in person

As for problems. The main are gaskets. Valve cover gaskets and LIM. Most of the time the valve covers are in good shape. The transmission can go out on these car sometimes, but with good care and fluid changes they will last a very long time.

[Madness]

For the air intake just go cheap and make your own or just go on ebay and look up AIR INTAKE FOR GRAND PRIX. It just a pipe with a filter and works great and you should get better milage with it.
Heres a link: Air Intake Pontiac Grand Prix SE GT GTP 1998 1999 2000 : eBay Motors (item 350216994722 end time May-18-10 20:27:24 PDT)

I checked out this e-bay item and noticed it appears the filter is open at both ends? What am I missing? How does this filter the air going in?

[Fivefingerdeathpunch]

I checked out this e-bay item and noticed it appears the filter is open at both ends? What am I missing? How does this filter the air going in?

Its called a open cone filter. They work the best and it will filter the air just like a normal one.
Looks like this.http://www.rpmoutlet.com/images/mtb990098.jpg

[Biohazed]

X3 definatly check the LIM gaskets!! and welcome

[prixgt01]

ok sweet thanks for all the replies. Now what about the top end swap that was stated above what does that involve? And also if you delete the u bend with a sensor on the top of it do you have to re drill a hole for that sensor not to throw the ecu off?

[JoRoW99]

why has no one pointed him to this yet?
http://www.grandprixforums.net/f81/s...car-17482.html
That will teach you a lot about your car, read it more than once.

http://www.grandprixforums.net/f17/t...lots-7763.html
That will also teach you a lot, it explains what a top swap is. But basically, its taking the supercharger off of a GTP and putting it on your motor, to make you go fast.

[prixgt01]

thanks jorow90 for for the great advise. Im proud to say im a new grand prix owner went and picked it up today. Question for anyone is what type of oil is best for the var, spark plus and wires? anything else you guys suggest for tune up wise that i should know? thanks agian

[GAFF]

One thing that wasnt mentioned was pay attention the trans and figure out when or if it has ever been rebuilt or replaced.

[Odi]

spark plugs - copper ones. 3800 love copper spark plugs like Autolite 606. as for the wires, the stockers are fine. replace them if you want to with the oem ones. oil - i use castrol in my car (not the high milage one) and im changing it every 3000-3500 miles. hit 145 000 and the car is a dream.

[Poil336]

Colder air will give you more power but can decrease gas mileage. Hot air will give you better mileage but a little less HP. I am not genius about the reason why its that way but its true. Maybe someone else can give you the exact reason why.

here's my attempt at a physics lesson.
imagine a certain mass of air. at a certain temperature, it would take up a certain volume. as temperature changes, so does volume. with a lower temp comes a lower volume; a higher temp means a greater volume.

now think about the combustion chamber of the motor. as the piston reaches the bottom of its cycle, the combustion chamber is at it's maximum volume (for this example, we'll ignore any knock retard effects). the way to get the most force from the eventual explosion is to have the most gas in the chamber, and since colder air takes up a smaller volume per unit mass, you maximize the amount of air/fuel mix in the chamber using colder air.

since warmer air takes up a larger volume, the chamber fills up quicker with less air/fuel mix, meaning you get to save a little bit of gas. but since there is less fuel, you have less force from the explosion, therefore less power.

in the real world, the temp difference between a fenderwell intake and a short ram or open cone intake isn't really that great. and because KR exists and limits the amount of gas you can compress before it combusts and shatters your piston, the two aren't much different. you can really just adjust timing to counteract the slightly higher intake temps from an open cone. as long as you can get sufficient air to the motor, you're good.

[Fivefingerdeathpunch]

That was pretty well said.

[prixgt01]

thanks for all the replies they all will be well used and stored in the memory bank

[JoRoW99]

I switched to synthetic oil after about 95K miles and havent had any problems yet, but im still on the first batch. I would go with the cheap lifetime warranty wires, the expensive ones only look cool, they wont give you any type of performance gain.

[prixgt01]

[QUOTE=JoRoW99;365100]I switched to synthetic oil after about 95K miles and havent had any problems yet, but im still on the first batch.< what weight are you using? and i just found and oil leak dripping down on the bottom of the block any ideas? Oil pan gasket, drain filter? thanks?