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99-LS1-SS
11-04-2008, 08:10 AM
I got permission from Driver72 to copy and paste this over here. Maybe he'll join and answer questions. Here is the review that one of his friends gave when he test drove a GXP.


Driver72

"Ok, here goes.
I just got off the phone with him.
It was raining on and off here in LA all day long today.
I thought maybe they'd cancel the photo shoot and drive, but they didn't.

The car was a Blue Pontiac G8 GXP with a 6MT tranny.

Yesterday it was at Willow Springs doing the performance testing for the magazine, they did not release the details of the testing, but know this, the car magazine allowed the photog and driver today to take their new $5000+ VBox (professional unit) along with them today.
On a damp day here in LA on a nice straight road in Malibu, a non professional driver (but he's a friend of mine and like me we've been car enthusiasts for a long time and he knows how to drive well) was able to get a
0-60 in 4.79 seconds. This is an uncorrected time and done on a road that was recently damp, with a driver who was driving the car for the first time.
I'd bet the official times from the magazine are probably in the 4.6 second range when done on a track with better conditions.

He said the 6MT is great. Very smooth and easy clutch.
The tranny is the same from the Corvette, but they mentioned the clutch is much smoother and easier than the last Corvette he drove.
He mentioned he was able to get this time by launching somewhere around 2600 rpms and not slipping the clutch but not dumping it either, but a smooth progressive and quick release.
He was disappointed that the car came with 245 Bridgestone rubber ALL around.
He thought with 265 or wider rear rubber he'd have even better off the line times.
He did say the 245 rears did make for some entertaining sliding.

You are able to turn the stability control completely off, but it's either on or off.
With it on, he said it wasn't overly intrusive, and allowed a bit of slip, but not much.
Personally I think it would of been nice to have a "sport" mode where it wasn't completely off, but did allow more slippage than when it's on.

He said the sticker price was $36k on the car and it's only real option is the moonroof (other than transmission choice). No NAV.

He said, compared to the G8 GT (which the exhaust note is a bit soft) the GXP was near perfect. He thought it could MAYBE use a bit more sound, but that would only be for those who really like a rumbling exhaust. But he didn't feel any need for it to be any louder for a stock V8 sedan.

Suspension wise, he was impressed. Doing a bunch of side to side chicanes on the canyon roads he said it handles great. The magazine won't allow them to cross the double yellow line for the photography, but he said once he was still able to run the car hard around corners and sweepers and for a 3850 lbs car it felt great.
He did say the rear suspension seemed a bit high though.

He loved the seats too. Not sure if they are the same in the G8 GT but said they were comfortable and the bolsters were more than sufficient for hard canyon driving.

That's about it.
You'll probably see the full test by this magazine in a couple months.

Well hope this gives you guys a bit of an insight into the G8 GXP.
You'll definitely have to pick up a copy of the magazine when it comes out. But I'd bet if you are a car enthusiast in the slightest that you guys already have a subscription to this magazine already anyway.

Take care.

PS Maybe, just maybe one of the two guys that were out with the car today might be inclined to post up too, but he'd probably rather remain mum."

Blackdevil77
11-04-2008, 04:15 PM
What is redline in the GXP? I'm guessing it's higher than the 6000 in the GT with the AFM cam+lifters

99-LS1-SS
11-05-2008, 01:02 PM
I think I heard somewhere that it was 6500.

Andy@Livernois
11-05-2008, 01:07 PM
6500 seems about right...

http://media.gm.com/us/powertrain/en/product_services/2009/HPT%20Library/Gen%20IV/Gen%20IV%20Car/2009_62L_LS3_%20Pontiac_G8_GXP_n.pdf

Driver72
11-06-2008, 09:59 AM
Hello guys, I've been invited to join by Grrr8.

I will answer some of these questions if I can.

He told me the redline was 6700 rpm and fuel cut off was around 7000-7100 rpm.


What is redline in the GXP? I'm guessing it's higher than the 6000 in the GT with the AFM cam+lifters

99-LS1-SS
11-06-2008, 05:45 PM
Thanks for joining us Driver72. Did he give an indication of how the car drove, comfort-wise? Was the car hard to launch or was it just slower due to the narrow tires? Thanks again.

Driver72
11-06-2008, 07:23 PM
Thanks for joining us Driver72. Did he give an indication of how the car drove, comfort-wise? Was the car hard to launch or was it just slower due to the narrow tires? Thanks again.

He liked the way the car drove.
Said it was comfortable when just cruising, but when you flung it into a corner it handled very well for a car of it's size and weight.

He said for the 4.79 0-60 time he got (again on a slightly damp road and not corrected for weather) he had to not dump the clutch but not slip out slowly either. Kind of a fast but progressive release.
I think I put it in the original post, but he did so launching it at like 2500 rpms (again see my original post for the exact rpms he originally told me).
He was just disappointed that it didn't come with staggered wheel tire sizes.
He mentioned 245 series rear tires on a car of this size and power was not large enough.
He said, he'd love to see what kind of 0-60 he could cut with 285's on the rear.
I mentioned, they probably wouldn't fit. He said he looked and there was "tons" of room and was sure they would.
Personally I think 285's would be too much and would affect the ride (since you'd have to have a REALLY low profile tire then to keep the overall diameter in check. But I bet 265's on the rear would be ideal. **Edit, 275/30/19's are the ideal replacement for the 245/40/19's the stock rear tires come with. Would be ideal.:::

He loved the clutch and shifter too.
It reminded him of his V8 S4.
He said the shifter was no Acura/Honda (like the new TSX he also drove for the magazine before it was released) but that it was better than the Corvette he drove.
Even though it's the same gearbox, I think Pontiac made "adjustments" to the take up and release of the clutch.
He said he had not misshifts or grinded gears either.

p71
11-07-2008, 05:29 AM
couple things... the numeric profile of the tire might be different, but the sidewall height, the biggest determinant when you are considering a tire as a component of suspension, would have the same measured height (being as how tire sizes use the second most ridiculous naming convention in the history of history). Secondly the trannies are not quite the same unless there has been a radical change in corvettes whilst I was not watching... corvettes use a transaxle not a conventional transmission, so whilst the tranny is in some way similar it is in some ways different... like it has a torque tube instead of a driveshaft, is mounted backwards in the rear of the car and is integrated into the rear differential. These subtle modifications may have lead to the difference in feel.

wreckwriter
11-07-2008, 05:33 AM
(being as how tire sizes use the second most ridiculous naming convention in the history of history).

What's the first?

Driver72
11-07-2008, 07:57 AM
couple things... the numeric profile of the tire might be different, but the sidewall height, the biggest determinant when you are considering a tire as a component of suspension, would have the same measured height (being as how tire sizes use the second most ridiculous naming convention in the history of history). Secondly the trannies are not quite the same unless there has been a radical change in corvettes whilst I was not watching... corvettes use a transaxle not a conventional transmission, so whilst the tranny is in some way similar it is in some ways different... like it has a torque tube instead of a driveshaft, is mounted backwards in the rear of the car and is integrated into the rear differential. These subtle modifications may have lead to the difference in feel.

Thanks for the clarification on the tranny difference.
But yes, I'm aware of tire sizes and what they mean.
It was just a bit silly to put 245/40/19 rear tires on the GXP when they could of put 275/35/19 rears on and gotten a fatter tire patch but pretty much the exact same overall diameter of the 245/40 tire. Better traction this way and less likely to power oversteer when getting on the throttle coming out of a corner.
If I was to get a GXP switching to the 275/35/19 rear tires would be one of the first things I'd do.

-Ray-
11-07-2008, 10:57 AM
What's the first?

Inch for wheels, metric for width and aspect ratio for height.
Kinda weird now that I typed it.

p71
11-08-2008, 12:08 AM
I am going to stick with Horsepower

LDV60
11-09-2008, 07:00 PM
275/35/19 is a pig of a size to buy. In the Australian car market there are only 3 cars that have this size OEM (BMW M5, Aston Martin DB9 and HSV Clubsport). I know that you guys get quite a few more offerings in your market space, but that could be a reason for it.


HSV also have contracted Bridgestone to produce the RE050A in this size specifically for the Clubsport. There may be some sort of limitation on providing this size to "other" manufacturers in this size in the Australian.

Got to say though that the 275 is a great tyre for these cars. Holdens have been notoriously under gripped in the past but I think this combo works great.

bobyoung
11-17-2008, 08:49 PM
I gotta keep the miles low, I'm seriously thinking of trading the G8 for one of these when they become available. I have 4500 on it already and I have only had it now for a little over two months.

Andy@Livernois
11-18-2008, 04:40 AM
same deal with my TBSS i had 3500 miles on it the first month cause we loved driving it so much...