I finally lit the fuse!!!!

[51gxp]

Well fellow GXPers, my car passed 500 miles a couple days ago, so I had the dealer change the trans and diff fluids this morning (to the tune of $240.00. At least they could have kissed me first ). Anyway, drove it for around 10 minutes to get all the fluids up to temp. Left a stop sign and at around 2000RPM, finally dropped the hammer. Let's just say first gear is real short!!!! Grabbed second, and I was near red line in a couple of seconds. Hit third, and was at 80MPH and still going strongly in what seemed like an instant. The power delivery is strong and linear right to red line. Rolling acceleration in 2ND and third gears from around 3000 RPM on up is particularly impressive. Because of the linear power delivery combined with the great suspension, the sensation isn't scary in the least (darn it. Gotta add more power ). It is very addicting, however !!!! For those waiting on delivery, all I can say is the wait will be worth it!!!!!

The only sour note I have to report is the "soot" in the exhaust outlets that others have reported (and I observed as well). The dealer said it was normal. Horse hockey. At this rate, the exhaust system will look like a couple of straw-diameter outlets in a couple thousand miles. Oh well. I made sure they noted on the work order that their assessment was crap, and assume GM will take a nice big warranty hit once they get it sorted out. The good news is at this point, the performance is more than "adequate"

[Beau]

All direct injection motors have this trait. Something you may have to live with.
Anywas, Im not sure why you replaced those fluids, I don't think its part of the sched. But whatver is gonna make you feel more comfortable, additionally. Congrats man. You will definatly require more power soon, but I think there will be some there for ya :]

[Windblade]

Sounds like the car has the umph. I was wondering though what is your impression of the dual exhaust sound compared to the base Sol. Is it raspier, louder, throatier? PS, I think you meant lit the fuse.

[RODEO]

Originally Posted by Beau All direct injection motors have this trait. Something you may have to live with.

are you referring to the soot? DI has this trait? Interesting........

[51gxp]

Originally Posted by Zolsol Sounds like the car has the umph. I was wondering though what is your impression of the dual exhaust sound compared to the base Sol. Is it raspier, louder, throatier? PS, I think you meant lit the fuse.

Oops, spell check thinks "it" is a word. What's with that ?? Yes, exhaust definitely sounds deeper, more purposeful than regular Sol. I wouldn't say louder, just more "businesslike"....

[51gxp]

Originally Posted by Beau All direct injection motors have this trait. Something you may have to live with. Anywas, I'm not sure why you replaced those fluids, I don't think its part of the sched. But whatever is gonna make you feel more comfortable, additionally. Congrats man. You will definatly require more power soon, but I think there will be some there for ya :]

Hi, Beau. I replaced those fluids to get rid of any manufacturing or break-in "nasties" before pouring it on. I hope to keep my toy for a long time. Just being cautious. If you'd spent as many years around powertrain manufacturing as I, you would probably do the same .......

[Mallard]

Originally Posted by 51gxp Hi, Beau. I replaced those fluids to get rid of any manufacturing or break-in "nasties" before pouring it on. I hope to keep my toy for a long time. Just being cautious. If you'd spent as many years around powertrain manufacturing as I, you would probably do the same .......

Yes, as Beau said, the soot is nothing to worry about and is a natural result of the how the fuel burns in a DI engine. On top of that it's turbo, so it's probably running rich under boost, which will also cause more soot.

You guys should have driven my Mazdaspeed Protege. Every time I washed the car I would clean the exhaust tips and the rear bumper would be scrubbed really good.

[51gxp]

Yes, I understand the exhaust tips and outside can be cleaned. I'm concerned with the particulate accumulation through the rest of the exhaust system that can't be reached (or cleaned). I find it hard to believe what I'm seeing is "normal". At this rate, it will take no time to reduce the diameter of the whole exhaust path...... This will have to affect performance eventually. Hope I'm wrong. If not, there's 5yr. / 100,000!!!!

[Mallard]

Originally Posted by 51gxp Yes, I understand the exhaust tips and outside can be cleaned. I'm concerned with the particulate accumulation through the rest of the exhaust system that can't be reached (or cleaned). I find it hard to believe what I'm seeing is "normal". At this rate, it will take no time to reduce the diameter of the whole exhaust path...... This will have to affect performance eventually. Hope I'm wrong. If not, there's 5yr. / 100,000!!!!

You have to remember that the exhaust gas farther up stream is very hot and moving a lot faster. It settles more at the back of the car because the charge is cool and slow moving.

Honestly, it's normal. There are plenty of diesels that run for 100's of thousands of miles and have no issues of reduced exhaust flow because of soot build up.

[achieftain]

I'll back that up with the diesels and also Superchargers on gas engines. Be thankful it is at the tips and not filling the cat and the muffler.

[MyNewSolstice]

Originally Posted by RODEO are you referring to the soot? DI has this trait? Interesting........

I believe tyhe soot is an issue due to the cars running rich due to ECM resettings...PS you will be called in by the dealers to deal with this...

[LatinVenom]

Yes but a diesel engine is a different animal, I will still wait for Frank to come back with an answer from the GM folks and also from the Bosch people.
By the way I find the sound of the exhaust to be more mellow than the NA Solstice, it purrs(spelling) at low Rpm.
I hope my NEW mod will not be to bad in sound.

[jimbo]

Thanks for the great report.

As for the soot, I can't possibly know how it feels. You want a new car to be perfect and anything imperfect or out of the ordinary is both annoying and frustrating. Still, between the clunk, the whine, the leak, and soot, I would pick soot.

Every imperfect car has its character. I guess this is part of the GXP's. If DI causes soot, then you can eventually look forward to this being typical of much of GM's cars and trucks. It seems to be the wave of the future for all motors.

[Mallard]

Originally Posted by LatinVenom Yes but a diesel engine is a different animal, I will still wait for Frank to come back with an answer from the GM folks and also from the Bosch people. By the way I find the sound of the exhaust to be more mellow than the NA Solstice, it purrs(spelling) at low Rpm. I hope my NEW mod will not be to bad in sound.

But the fuel delivery is very similar and the burn is very similar as well. It has to do with a) running richer under boost and b) how the fuel droplets combust.

Remember, in a DI engine the air and fuel have to mix incredibly fast, hence the importance of high fuel pressure in order to get good fuel atomization (really small fuel droplets). In a port injection engine the air and fuel can mix completely, becoming more like vapor and allowing it to burn more completely. "Soot" is unburned hydrocarbons that result from incomplete combustion. This could be from running richer then 14.7 a/f (which all cars do under high load) or from an actual fuel droplet burning.

When a droplet burns, it burns from the outside in towards the center. (Picture the drop of fuel as a globe.) The fuel on the outside of the sphere burns completely and energy is continually lost until you're left with the fuel in the center of the globe...which burns incompletely and produces a piece of soot. That's the mechanics of a diesel burn and my assumption is it's the same with DI. I am talking to some of my other friends that deal directly with engine theory and will update you if I end up being wrong.

Latin and MyNewSolstice - The production hold on the GXP has nothing to do with soot or the engine tune. That's all I can say about that, but if FrankC5R wants to elaborate later he can. It's nothing to worry about. Your cars are fine.

[MyNewSolstice]

Mallard the hold is due to "things working too efficiently" and making condensation...I know why but the soot is the soot and to deal with it would require an ECM flash if you want to deal with it....