Pontiac 3.8SC More HP/Trq?

[BobGPz]

Does the 3.8L Supercharged Pontiac Grand Prix SE motor have more power than our 3.8 SC's? Just curious if anyone knows...what kind of supercharger are they running?

[J57ltr]

Last I remember the Gen 2 was 240hp, don't remember torque. The Gen 1 used the M62, but the Gen 2&3 use the M90.

Jeff

[Thomas A]

Well, actually it's the GTP, not SE models that are supercharged. The '97-'03's were rated at 240bhp while the 2004 models got bumped up to 260bhp.

Thomas

[Digitalchaos]

I believe both the '97 & '04 had around 280 ft lbs of torque. I know they were not as much as the SCs.. it seems to be a trade-off for horsepower.

www.edmunds.com

[pdennis93]

i think the GTP had more hp than our car stock because we gained 70hp over a 140 horse motor, while they gained only 40hp because of not having the intercooler, BUT they started off with a 200hp power plant.

[Phil Kuhn]

Digital is correct. They are running about 280 ft-lbs of torque.
That is less than the SC by at least 20-40 ft-lbs.

[BobGPz]

Guess a Pontiac M90 would work on our SC if can find one for parts? Actually I could SC my Toyota pickup w/ pontiac motor setup:D

[David Neibert]

Guess a Pontiac M90 would work on our SC if can find one for parts? Actually I could SC my Toyota pickup w/ pontiac motor setup

Bob,

The GTP uses a different case style, that has the exit air flowing down directly into the intake manifold. To use that blower on an SC you would need a custom intake manifold like Manny's inverted blower.

IMO, there is nothing to be gained unless you also add a liquid IC core under the supercharger.

David

[BobGPz]

Was just curious as I saw a 3.8L motor with a SC on top for sale at a "U-Pull It" wrecking yard. Did a double take before I realized it was a Pontiac motor. Think I'll leave my setup as is, unless motor goes, then a 460 Big Block would be fun! Hell, if it can fit into a 72' Toyota Celica, I'm sure it can fit into my Thunderbird SC.

[pearl95sc]

Well, the lack of torque in the gtp's and ssei's helps in their slowness. With the SC in bone stock trim, I would always whoop one. They also have the front wheel drive advantage on the grip and go too. Go figure.

[91BLOWNSC]

Originally posted by pearl95sc
Well, the lack of torque in the gtp's and ssei's helps in their slowness. With the SC in bone stock trim, I would always whoop one. They also have the front wheel drive advantage on the grip and go too. Go figure.

Slowness? Completely stock, the only SC that will have a chance would be a 94/95 model (maybe a early model manual if it was a freak) and you could not "whoop" one unless it wasn't running right. My friend owns a 2000 GTP that ran 14.8 @ 94 mph completely stock. Ran a 14.6 with the U-bend removed and intake. And a 14.1 @ 97 mph with a simple pulley swap. His next computer mod for roughly 200 dollars is going to shoot him into the 13's. Hes pushing 12 PSI w/o and intercooler. Though that will hurt him in the summer; in this 10 degree weather were having the thing is vicious. I have a pulley, exhaust, intake and only ran a best of 14.8. The GTP dynoed with that done and had 242 hp at the wheels and 271 ft/lbs of torque at the wheels. Posted stock times are supposed to be 15.1 @ 91.

I doubt my modified SC could have beat him stock. I have raced other GTPs though, and readily beat both of them by about 2 car lengths with my current modifications.

With about 400 pounds less than us, the extra torque is in proportion to ours, AND they have more horsepower which only equals better times.

[Mr1der]

didn't the Ponchos have a lot of factory freaks?

and are the trannies still junk? I was thinking they used the same as the Luminas, which sucked...

[David Neibert]

My friend owns a 2000 GTP that ran 14.8 @ 94 mph completely stock.

My wife's 99 GTP ran low 14s bone stock and has ran a best of 14.1 @ 96 (cold fall day). These runs were against SCs at a couple of our mini-meets here in St. Louis. If not for the front wheel drive traction problems, it would be even quicker.

In an effort to get her car into the 13s I added a custom 3.2 pulley. It made the car slower (low 15s), so I made another one that was 3.6 dia. (slightly smaller than stock) and now it's back to running mid to low 14s.

David

[Steve Richards]

Hey Dave,
Do you know where we can get one of those "liquid IC cores"???

[silversc90]

The gtp's you have to watch out for are the 98-99. From my experience at the strip (getting spanked). They seem to benefit the most from a pulley intake and exhaust mods (sounds familiar) low 13s with just those. On the streets gtps suck from lack of tq.


And you guys lookin for a intercooler what about the cobra's and lightnings?????

[David Neibert]

Hey Dave, Do you know where we can get one of those "liquid IC cores"???

No I don't, but I would start with call to Spearco if you were serious about finding one.

David

[Steve Richards]

I thought about them but the intercoolers look to be too long to fit in our intakes. As well, I think we'd have to fabricate an adaptor plate that would raise the blower too high for even my 1.5" cowl hood.

[supafly223]

yea the gtp's have 240hp/280tq...... but were also only running 6lbs of boost to the SC's 12. little somethin to think about......

[BobGPz]

I wonder what 12 psi's would do to the Pontiac motor? The Pontiac's must have a higher compression ratio than our SC's then. If not, I would imagine there is a significant amount of improvement that can be made from a pulley/intake upgrade on the Pontiac..Think it was SilverSC90's post also made mention of this.

[supafly223]

i dont believe the internals of the GTP's are upgraded like the SC's so i probably wouldnt run more than 10psi without upgrading some stuff. they just threw a supercharger on a regular 3.8.

p.s. my 99 gtp would take my 90 SC without a problem. there both stock.

[BlackbirdSC]

The GTP's use iron heads where the SC's are aluminum. That would cause some problems with raised boost levels. More than likely, when Dave put the small pulley on his it was pulling a stack of timing out to keep it from blowing apart. With an IC, it would have added some HP for sure. The GTP exhaust ports are way WAY better than the SC's stock for stock.

And remember all GTPs were auto's and I believe had traction control (not sure if it was all of them). So if an auto GTP with TC is running against a 5spd SC, that chance of the SC 'missing' the launch or a shift are much greater than the chance of the GTP doing the same.

The last thing I'll say is the SC is late 80's tehnology and the GTP is mid 90's tech. I'm rather surprised the SC is as close as it is to an almost 10 year newer design (15+years when compared to an '04).

[pearl95sc]

As said earlier, freaks, mine was one, still is. In bone stock trim, I could chirp third gear, and was able to hit 145mph several times, with 4 people in the car too. With just myself, I hit 151mph. So maybe I did have a factory freak, no complaints from me. As far a street racing, I never had trouble beatin a gtp/ssei/regal gs that was in stock trim. I even had a guy in a gtp, with exhaust, brakes, pulley, intake, and a few other things back down from a race because he was that sure my car would beat him. When I first got my car, I raced an auto z28, newer, lt1 engine, and from a light, he only got me by 3 cars. I was at 80mph on a regular busy street, and we both slowed up at that point. Go figure.

[BlueThunder90]

Originally posted by BlackbirdSC
The GTP's use iron heads where the SC's are aluminum. That would cause some problems with raised boost levels. More than likely, when Dave put the small pulley on his it was pulling a stack of timing out to keep it from blowing apart. With an IC, it would have added some HP for sure. The GTP exhaust ports are way WAY better than the SC's stock for stock.

And remember all GTPs were auto's and I believe had traction control (not sure if it was all of them). So if an auto GTP with TC is running against a 5spd SC, that chance of the SC 'missing' the launch or a shift are much greater than the chance of the GTP doing the same.

The last thing I'll say is the SC is late 80's tehnology and the GTP is mid 90's tech. I'm rather surprised the SC is as close as it is to an almost 10 year newer design (15+years when compared to an '04).

I know a couple guys and have raced them at the track with their GTP's and it's impressive what you can do with them for a little amount of money.

For less than 1k, you could have a GTP into the low 13's with ease and they can handle the added boost with no problems.

Their only downfall is the trannys as they don't take well to constant track beatings :)

[silversc90]

And while were on trannies, I bet its a pain to swap gears.

[BobGPz]

Blue Thunder, that's a nice looking SC and engine compartment to boot.

[BlueThunder90]

Originally posted by BobGPz
Blue Thunder, that's a nice looking SC and engine compartment to boot.

Thanks :D It's For Sale too!

[Stephen Heinze]

GTP's are very fast...but, there engines do not last as long due to the supercharger...my friend has 120 thousnad miles on his 97 and it is up for a rebuild...they are a good car for the money,,,but I like a little more sporty set-up...two door...rear-wheel drive.

[silversc90]

What are you lookin to get out of your bird???