Hey everyone. I'm new to these forums, but not new to the Grand Prix. I used to own a 1998 GTP coupe, but that turned out to be a bad car so I sold it. After the grand pric I figured I'd try out something diffrent and bought a 02 WRX Impreza wagon. Really fun car. Although the car is great it gets bad MPG and I don't like to deal with the turbo lag. I'm going to sell the wrx soon and be buying a new 06 Grand Prix GT soon after. Now that yall know my life history lol :p heres my questions.

How good at the 06 3.8 S/C engine? Any problems I should be looking for when buying one? How good are they on gas? I drive about 25-50 miles every weekend and I don't exactly like to do speed limit . I'm usually doing 70-80 mph. So what kinda MPG will I be seeing from a grand prix at those speeds? Thats all on the highway btw. Last question. Are these cars as fun as the older models? I used to rip things up with my 98 gtp was wondering if they toned the 06's down since they made them only 4drs.

Thanks for any info
Chris

Welcome!

The 3.8 is one of the best engines ever made. It will last forever with regular maintenance. Make it last longer by using synthetic oil, if you can. GM can't make a transmission to save their lives, so watch out for problems with that. You should be fine if you don't beat on it regularly.

You should net from 21+ MPG at the speeds you mentioned, but remember that the faster you're going, the less you're getting.

They didn't tone down the S/C engine for 04+. In fact, they ramped it up. It has an additional 20 HP, though the 280 torque stayed the same. They're just as much of a beast and it doesn't matter how many doors it has, it'll be blowing them off anyway.

People need to stop looking at the number of doors a car has; there are tons of sedans that can embarrass their coupe brethren.

I totaly agree with that statment hah. I've seen some nice numbers out of 4dr GTP when I had my old coupe. I wish they had made a coupe vesion in the 04 body style, but not because I think they are slower then coupes. I think the 04 body style would look really nice as a coupe. I don't care much for the way the G6 coupe looks.

Well from what I just heard... I can't wait to get behind the wheel of one of these bad boys

Since I've owned a 98 gtp befor I pretty much know the way mods should go for one of those. (pcm, exhaust, intake, smaller pulley, maybe an intercooler, and so on).

Is there anything diffrent I should get to keep the reliabilty of the car, but get that few extra horses out from under the hood of one of the 06's?

Well looks like my WRX isn't willing to be sold without a fight. It had been making a weird crackling noise since last night. Found out today from the dealer the turbo is blown and its going to be $1500 to replace it... Sets me back by a month or so from getting the Grand Prix...

Stupid Turbos

One thing about the 04+ is the torque management is in full effect. Because of that the initial off the line pull you were use to on the older GTPs isn't there and is a big complaint. But with a reprogrammed PCM will cure that and you'd be very happy.

I regularly cruise my 01 GT at around 75mph...I've taken it on three different vacations and I've never checked the gas mileage and gotten under 26mpg highway. I'm sure I get less than that back and forth to work since I like to play with the happy pedal...but overall I think you'll find the mileage is great considering the performance these cars deliver.

Well looks like its been taking longer then I thought to get the WRX sold. Its up on autotrader.com and in the Autotrader book. So far only one call and he didn't sound like he wanted it. Hope it sells soon. Getting sick of driving a manual car . Although now the G6 is catching my eye.. might have to go check out one of those when I check out a Grand Prix :p

O6 S/C grand prixs are awesome, my friends brother has one and that thing gets up but far as gas mileage, it should not be to bad probably 20 mpg and up if your under 70 miles per hour.

I have had nothing but a great time with mine and I have met lots of great people through the car!

Well looks like I'll be trading in the WRX since I haven't had a buyer yet. Its gone from 65,000 miles on it to 70,000, and I don't want to put to many miles on it if I'm going to trade it in. One of my friends fathers works at Monday Chevy, and they have a 2006 GP GT. Gonna go take a look at it soon and find out how much my car would go for if i traded it in. Probably not more then $8,000. Can't wait to get behind the wheel of a GP again though

I have a 2004 GT2 and I wouldn't give it up for the world. I do a lot of expressway driving. Over 30,000 miles a year. I don't rag on my car, but I drive usually 75 mph. I average between 29 and 31 miles per gallon driving at that speed. When I combine it with some city driving, it drops a mile or two.

I owned a 2001 GP before this one. I actually think it cornered better, but the ride was very bumpy. The 2004 has a nice balance of handeling and ride comfort. I don't think you'd be disappointed.

Another thing is that there are a lot of cool upgrades you can do. And not just for performance, but for bling! I just started putting some cool things like aluminium motor mounts and aluminium support bars. Chrome oil breather. The chrome grilles and headlight covers. www.3800performance.com is a great place to get some nice upgrades as is pfyc.com.

Hey, how do you guys add the pictures to your posts?

Whats the diffrence between the 2004-05 GTP's then the 2006 GT? I was looking at them both and I really can't find a diffrence other then the 04-05 being called GTP's and the 06 being called GT...

I was just wondering because there are alot more 04-05 within my price range then the 06 with about the same amount of miles

I had a 99 runnin 13s on good street tires. I had a lot of fun with that car and it sounded like a trans am or z-28. I have on 05 GXP now and am waiting for the G8 (wish they had a better name). I've made these pics as small as I could. Here's the new pedals I just got from Ultimate Pedals in West Palm Beach, Florida. Custom Made. I have deleted my res. and have two polished Magnaflows on the way with a Hogan Perf. 3" downpipe and a K&N CAI. Porgramming is next after dyno runs (Predator needs to make one for my 05'). I also have Lumiinics 9007 ultra white headlights, H3 titanium white foglights, and a gun metal weave overlay kit for sale for 97-03 G.P.s (all brand new).

I don't like the GXP's with the DOD V8's. I've heard of nothing but bad about that system. Besides, I've always loved the way the S/C sounded on the 3.8's with a good CAI

So can anyone explain to me whats the diffrence between the 04-05 GTP's and the 06 GT's?

I haven''t had any problems. This motor is a baby Vette motor. I live in an extremely hilly area, get 16mpg in the city and close to 30mpg on the highway. Beleive me, I miss my 99' and suprising those WRX and Evo guys once I got traction. The whine of my S.C. was one of the best parts about that car. But the internals are not made for all that horsepower as I blew my first motor. They are reliable as hell though when left alone.

The difference between the 04-05 gtps and the 06 gt is just the badging on the car. The 06gt is supercharged just like the 04-05 gtp's and they have the same horsepower. They drop the GTP badge for 06 and up until the new G8 comes out which will replace the grand prix in either 2008 or 2009.

Thanks for the Reply. Thats what I thought was the diffrence. Still tring to sell my WRX : / cant wait to get a GP again.

Should I be worried that since the G8 is replacing the GP that parts are going to get more expensive?

So I know I don't have a Grand Prix yet, but I wanted to know a few things about mods. What kinda mods will I have to do to be able to run a 3.0 or smaller pulley? I know even stock I wanna get an intercooler, but what else can I do to be running Knock free? Also how will the tranny hold up under that much HP? I'm guessing not very well...