The American M5- Pontiac G8 GXP

By Matt Stone

Photography by Julia LaPalme

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Strafing along a straight-as-a-string highway at about a buck-fifty, confusion struck. Were we in America aboard Pontiac's forty-or-so-grand, Pontiac G8 GXP circa 2008, or flogging a previous-generation BMW M5-a car that cost $70,000 eight years ago-on a German autobahn? Not sure. There's plenty of high-speed stability here, yet nice ride quality. A rumbling 400-plus-horsepower V-8 engine and six-speed manual transmission. Just-right-size four-door packaging, supportive leather sport seats, big brakes. Then the radio news guy said "Obama," and we realized that this was indeed the here and now. The badge on the steering wheel confirmed it. Mention BMW's seminal sport sedan and a Pontiac in the same breath? In this instance, without hesitation.

By now, you know the G8 is based on GM global rear-drive-chassis architecture born and bred in Australia. The base V-6 and 361-horse V-8 GT versions are currently on sale and playing to solid reviews. No, the G8 wasn't designed or built in Michigan, but that doesn't mean it's not a Pontiac. The car business continues to globalize, and variations on this theme are sold as Holdens, Daewoos, Opels, Vauxhalls-even Buicks in China and Chevys in the Middle East, so get over it.

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Under the hood of the GXP version rests as American a powerplant as was ever born, the latest and (nearly) greatest version of the Small Block Chevy, now called the LS3. At 6.2 liters, it grunts out 415 horsepower and the same amount of torque. Why "nearly" the greatest? Only the ZR1 and Cadillac CTS-v's supercharged version could be any greater. While the G8 GT is served only with a six-speed automatic transmission, clutch-and-shifter types can opt for a six-speed manual. We tested both and found their accelerative performance nearly identical, favoring the stick by never more than a tenth or two. And the GXP does its thing on regular-grade fuel, although it will earn a gas-guzzler tax (final pricing was not confirmed as of this writing).

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The GXP designation signifies more than an engine upgrade. With more go comes more stop, in the form of Brembo brake calipers, clamping 14.0-inch rotors front and 12.8-inchers aft. The G8 GT's suspension is already competent, but is retuned for GXP duty; the biggest change is larger front and rear anti-roll bars. The shocks are stiffer, and the rear balljoints are revised. Nineteen-inch alloy wheels are standard, as is summer-rated performance rubber (all season tires are also available). Calibration of the power rack-and-pinion steering is unchanged.

Styling cues are modest: The front and rear fascias are GXP-specific. There's too much fakery here for our taste: fake hood scoops, fake diffuser treatment in back, non-functional gills on the front fenders. But Pontiac isn't the only one to play that game. A matte-black or body-color side window surround would add back some stealth, but overall, the G8 GXP is a great-looking piece, with strong shoulders, a brand-proper face, and muscular stance.

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Inside you'll find thickly bolstered sport seats that really hold you in place. Rubber-trimmed alloy pedals look good and grip your Pilotis, but the beefy GXP steering wheel is a disappointment. It's square on the bottom and has cutouts for your thumbs, trying to emulate the tillers on banzai runners like the C63 AMG and BWM M3. But the lumps and bumps are all in the wrong place, creating more discomfort than benefit. The engine maxes out at 6600 revs, but you wouldn't know it from the redline-less tach that's marked to 8000.

Want more M5 references? The Pontiac is an inch and a pound larger in every direction, but nips the BMW in most performance categories. The previous-gen M5 ran 0-to-60 in 4.5 seconds; the trans G8 GXPs match that. The Bimmer grips to 0.84 g on the skidpad, the Pontiacs stick to 0.88-0.90 g. The BMW stops from 60-0 in 116 feet, the Pontiacs from 111-117. This is all the more impressive given the M5's near 200-pound weight advantage. Sure, the premium German performance kings have moved on from that previous-gen M5, but look what they cost. Before we forget, the LS3 sounds magnificent too; deep at idle, all pops and burbles on the overrun, yet never over the top.

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As noted, we sampled both transmission offerings and find each appealing for different drivers. The manual's short, meaty stick has a crisp, direct shift linkage, although several staffers feel the clutch takeup is light and lacking engagement feel. The gear ratios are spot on. On many cars, GM cranks in an overly aggressive throttle tip-in curve that gives the impression of super-quick response, fading to nothing as the pedal goes further to the floor. In this application, it feels unnatural and jerky. The G8 GXP is legit fast -- why fake it?

The automatic offers standard Drive, Sport Drive, and Manual modes. Drive is responsive yet smooth; ideal for normal running. Sport shifts quicker, holds gears longer, and downshifts sooner. Kudos for GM delivering a true manual mode, too. Click the shifter to the manual gate, and it'll hold gears right to the rev limiter without upshifting. And it won't downshift however hard you mash the gas. It's too bad that manual gate is on the far side of the console on left-hand-drive cars. Shifter paddles would have been fun too.

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There's no griping about the G8 GXP's ride and handling balance. In spite of some musclecar DNA, there's worldly breeding here. This machine is quiet at speed, with a minimum of wind noise or road rumble. The steering's weight, feel, and response are satisfying. The chassis tells you what's going on, and when the high limits are nearing. Weight distribution is a well-balanced 52 front, 48 rear. And it all comes in a package you can live with. Rear leg/headroom is excellent, even for tall occupants. The 17.5 cubic feet of trunk space is flat and useable. The audio and infotainment packages are acceptable, if not class leading, and we'd take a good touch-screen nav over OnStar's turn-by-turn directional guidance any day.

Pontiac's maximum strength G8 is a few details shy of legend, but that doesn't diminish its huge appeal and sophisticated, capable performance. The G8 GXP is a terrific, all-around sport sedan that runs with high-priced Germans. Its strong value message isn't a qualifier either, just a bonus. You could also think of the G8 GXP as a four-door Corvette of sorts. No matter, it is the best-performing, most well-balanced production Pontiac ever. That tells you all you need to know.

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2009 PONTIAC G8 GXP
Base price	$39,900 (est)
Price as tested	$41,500 (6M, est), $40,800 (6A, est)
Vehicle layout	Front-engine, RWD 5-pass, 4-door sedan
Engine	6.2L/415-hp*/415-lb-ft* OHV 16-valve V-8
Transmission	6-speed manual
Curb weight (f/r dist)	3969 lb (52/48%)
Wheelbase	114.8 in
Length x width x height	196.1 x 74.8 x 57.7 in
0-60 mph	4.5 sec
Quarter mile	13.0 sec @ 109.6 mph
Braking, 60-0 mph	117 ft
Lateral acceleration	0.90 g (avg)
MT Figure Eight	26.4 sec @ 0.70 g (avg)
EPA city/hwy fuel econ	Not yet rated
On sale in U.S.	February 2009
*SAE certified

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