The Pontiac G8 is a modern muscle car, with rear-wheel drive and a snarly V8. Under full-throttle acceleration, the new GXP model reminds us of a Corvette, pasting us into the back of the seat as a guttural roar comes from under the hood. In fact, the high-performance GXP is powered by a Corvette engine.
Bigger than the Mustang and Camaro pony cars, the G8 is a four-door like the Dodge Charger. It's smaller than the Charger or Ford Taurus, however, with exterior dimensions close to those of the Cadillac CTS and BMW 5 Series.
The G8 is attractive, smooth and muscular with an unmistakably Pontiac nose. The interior is comfortable and tidy, with good instrumentation and nice materials. The back seat is reasonably roomy and the trunk is big. The standard cloth seats are excellent. Leather is optional, and the 11-speaker Blaupunkt audio upgrade sounds great. The G8 has a comprehensive list of passive and active safety features, including head-protection airbags, electronic stability control, and GM's OnStar telematics system. We found everything in the G8 melds together nicely.
The G8 comes with a 256-hp V6, the same engine found in the brilliant Cadillac CTS. There's adequate power from the V6 engine. The base model lacks the verve of the GT model, however, partly because its five-speed automatic is less responsive. Still, it costs $3,400 less than the GT, and it delivers better fuel economy, earning an EPA rating of 17/25 mpg City/Highway.
The G8 GT features a 361-horsepower V8 that's smooth and responsive at any speed, and it makes for the most powerful sedan in this price range. Step on the gas: The thrill starts at the hood scoops, passes through the seat of the pants and spills from the GT's four stainless-steel exhaust tips as the countryside disappears rapidly in the rearview mirror. The GT's six-speed automatic is one of the smoothest, quickest shifting transmissions anywhere. Its handling character is taut, and its ride is comfortably firm. Thanks to GM's Active Fuel Management cylinder-deactivation technology, mileage isn't bad either, for such a powerful car. The GT delivers up to 24 mpg highway.
For 2009, the high-performance G8 GXP joined the lineup, powered by the same engine as the standard Corvette sports car. GM's 6.2-liter LS3 V8 generates upwards of 400 horsepower and 400 lb-ft of torque, and the GXP adds other performance upgrades, including an advanced Brembo brake system. It's hot. On a track it would be fantastic. Around town it feels like a muscle car. Order the GXP with the high-performance Tremec six-speed manual gearbox, and the clutch and strong torque conspire to make cruising around the neighborhood smoothly a bit of a challenge.
The G8 is Pontiac's first rear-wheel drive sedan in 20 years. It replaced the Grand Prix in the Pontiac line-up. We have Australia to thank for the Pontiac G8. It's built there by Holden, a division of General Motors, and is sold as the Commodore SS. It's been one Australia's favorites for years, and GM has had a long time to perfect it. North American shoppers seeking an engaging sports sedan with classic V8 thrust can now reap the benefits.
The G8 was launched as a 2008 model. For 2009, XM satellite radio hardware and Bluetooth connectivity come standard on all models.
The G8 may be the largest sedan in Pontiac's line, but it's not as big as traditional domestic full-size cars. Nor is it as big as current full-size models such as the Ford Taurus, and it has a much shorter wheelbase than the Chrysler 300 or Dodge Charger.
The shape of the Pontiac G8 seems exactly what it should be: muscular but smooth, edgy but reasonably subtle. Its styling should appeal to both exes and pretty much all ages. The G8 is unmistakably a Pontiac, especially from the front, with the signature split black grille and hood scoops. The scoops, though, are restrained, almost slits, as opposed to big bulges There's a spilt air intake, also in black, at the bottom of the front fascia. With the angled headlamps and front fender flares, everything is nicely balanced and just aggressive enough.
There's another set of openings in the front fenders, visible in side view right behind the wheels. The one on the left fender is a functioning air intake, while the right side is there merely to match the left. The G8's roofline sweeps enough to disguise the fact it has four doors, and the hips above the back fenders lift fairly high, flowing into a tidy spoiler. The G8 GT and GXP feature clear taillight lenses with four polished exhaust tips, while the base G8 has red lenses and two tips.
The wheels are 18-inch and 19-inch wheels are conservative, with either single, monoblock spokes or split twin-spokes. The wheels on the GXP are flashier.
The Pontiac G8 interior is attractive and nicely finished. The base G8 and the standard cloth interior in the G8 GT are similar. The GT has a bit more faux brushed aluminum trim, and it's tastefully done. The GXP distinguishes itself with two-tone sport seats featuring GXP embroidery and a color-coordinated gauge cluster.
All G8s come with XM Satellite Radio hardware and Bluetooth capability as standard equipment. The XM comes with a complimentary three-month subscription, but the owner will pay for the service after that. Bluetooth connectivity is integrated into the OnStar system and allows hands-free phone calls through your existing cell phone.
The seats are comfortable and power adjustable, four ways in the base G8 and six ways in the GT and GXP. The GT we tested had the optional leather seats, and they were good-looking in black. The seats offer good support for sporty driving. The GXP's sport seats offer more side bolster support for very hard driving, but they're harder to slide in and out of and they feel narrower.
Instrumentation is good, although not without flaws. There's a digital battery/oil pressure gauge in the center of the dash that's unattractive and not particularly useful, and the digital gear indicator is too small to read. The speedometer and tachometer are big enough, easy to read, and appropriate to the performance character of the G8.
The power window buttons are located on the console between the seats. Some drivers will like them there. We don't. They are more difficult to locate quickly without looking than door-mounted window switches, but they do allow the front passenger to operate all the windows, too, rather than just the front-passenger window. The emergency brake handle has been designed not to take up space, and is designed to mimic the grab handle on the right. However, like other similar designs the disguised hand brake can pitch your fingers when lowered, a good way to anger a harried driver.
The rear seats offer good legroom and decent head room. The driveshaft tunnel doesn't intrude too much in the center, either. There are heating and A/C vents in the rear doors, which also have good storage pockets. The front seatbacks have nets, which make easy storage for magazines, discs or plastic bottles.
Trunk access is wide and lift-over height is reasonable. The G8 boasts provides 17.5 cubic feet of cargo space, a foot or two more than most comparably sized competitors.
From the driver's perspective, the Pontiac G8 has lots of strengths and no glaring weaknesses. From the passenger's perspective, it's quiet and comfortable. From the driver's seat, the G8 feels smaller than it is, and that's a compliment. We'd call the G8 a sports sedan, at least from the mid-line GT upward. Next to the Cadillac CTS, it's the best performance-oriented four-door General Motors has introduced in years.
The 3.6-liter V6 in the G8 is same engine as that used the Cadillac CTS. It has dual overhead cams with continuously variable valve timing, and delivers 256 horsepower and 248 pound-feet of torque at a low 2100 rpm. The acceleration is good, but the exhaust note is raspy and not very pleasing when you're hard on the throttle. On the freeway at steady light throttle, the V6 is quiet.
What we liked least about the G8 V6 was its five-speed automatic transmission. The combination simply lacks the range and overall responsiveness of the GT's V8 and six-speed automatic. We got some good miles in the base G8, over twisty roads suited for sporty driving, and in Sport mode the transmission kept kicking down multiple gears like crazy. All it really did was make the car feel rougher than it is in Cruise mode.
Further, the suspension on the base G8 doesn't have the same taut feel as that on the GT. The G8 V6 is designed for drivers who love the style but don't need lots of performance. The V6 model is less aggressive in every respect. It gets better fuel economy than the V8 and it runs on regular fuel. The G8 V8 models require premium to achieve full power.
Before the GXP came out, the mid-line G8 GT was one of best performers in the class and we found it to be an enjoyable car to drive.
We drove the GT on one of our favorite roads, from San Diego to Borrego Springs, California, with little traffic, good visibility and the desert in full bloom. We finished without a single gripe about the performance of the G8 GT in areas that matter most: engine, transmission, suspension, brakes. The GT's 6.0-liter cam-in-block engine makes 361 horsepower and 385 pound-feet of torque. The torque peaks at a fairly high 4400 rpm, but the engine doesn't feel peaky all. Overall, the GT feels trim.
Before introduction of the new G8 GXP, the GT already had more power than any production Pontiac in history (take that, you Firebird Trans-Am Ram Air big honkin' hood scoop muscle cars). Yet the GT is totally tame until you want to use that power. Then it will accelerate from 0 to 60 in 5.1 seconds and knock off the quarter-mile in 13.8, according to Pontiac. And with all the torque on tap, the engine just lopes through places and situations that require other sedans to take a harder swing.
The 6.0-liter V8 features GM's Active Fuel Management technology, which allows it to operate as a four-cylinder under light loads: When cruising at a steady 60 mph, for example. The switch between four- and eight-cylinder operation is usually imperceptible, and it edges the GT up to its EPA rating of a combined 20 mpg. That's impressive for 360 horsepower, and it was unthinkable just a few years ago. We averaged 16.2 miles per gallon in our test GT, with a little freeway mixed into hard two-lane running for a couple of hours.
Maybe the best thing about the G8 GT is its six-speed automatic transmission. Pontiac has joined the slim ranks of the savvy by making a tight-shifting automatic with manual control that's absolutely faithful to the driver's commands. It makes sport driving a pleasure in the GT.
There are three modes for Pontiac's Driver Shift Control transmission: Cruise, Sport and Manual. Cruise is fully automatic; Sport is automatic with more aggressive shift points, and Manual is, totally, manual. In Manual, the transmission will short shift, or upshift under hard throttle below redline. Sometimes that's a useful and smooth technique, and far too many manually shifted automatic transmissions are programmed to disallow it. The thinking (by some engineer, somewhere) seems to be that hard throttle means full speed means full revs. No, not necessarily. The G8 GT transmission employs rev matching for smoother downshifting, and the revs are just right. There are rational limits to the manual control, however: It won't let you downshift if the lower gear would cause the engine to over-rev, but it will allow you to reach redline and stay there. It won't upshift for you, in manual mode, unless you move the shift lever yourself. The G8 doesn't offer the steering-wheel mounted paddle shifters often used with transmissions of this type, but we didn't miss them. And for fully automatic shifting, the Sport mode is actually useful. Some aren't, because they just make the power delivery jerky. Cruise mode is true, too, for smooth cruising. You don't feel each downshift at every red light and stop sign. This transmission understands gliding, and that may be what we like best. For all its sporting characteristics and effectiveness when shifted manually, the G8 GT's transmission can be as smooth and comfortable as any luxury car's when the driver is just plodding along. The GT transmission is the same one used in GXP, and it's so effective that we might take it over the optional manual, even if we didn't drive in traffic.
The GT's suspension is firm enough, too, and its handling is tight, but the ride is never uncomfortable. This as much as anything distinguishes it from Pontiac's previous efforts to build a sports sedan, and it's a function of good development work. The steering rack is mounted forward of the front axle, which Pontiac engineers say improves response. The engine sits low and rearward in the chassis cradle, and little tricks like a rear-mounted battery helped balance the car to a 50:50 weight distribution front-rear. The G8's body is built with 80 percent high-strength steel, which allows the suspension to do its job well and helps control interior vibration.
We found the handling confident, precise and sharp. The electronic stability control is tuned like that on some of the best European sport sedans. During our hard drive to Borrego Springs, the stability control activated maybe three times, and at just at the right times, as when the rear wheels began bouncing slightly from the road surface. In that situation, some systems will cut the throttle so much the car falls on its nose and makes you curse. Not so with the G8 GT, which cuts the throttle just for a split second and then lets you continue to drive the car.
We found the ride quality of the GT excellent. Compared to the Mercedes C63 AMG, a $50,800 challenger to the BMW M3 we tested on Arizona back roads the day before we drove the Pontiac, the G8 GT's ride is more pleasing, lacking all harshness. Yet despite the general comfort we never hit a spot where the G8 GT felt in over its head, as in being too soft in a hard corner. And we tried to find that spot.
The GXP is the hottest model and can accelerate from 0-60 mph in 4.7 seconds, says Pontiac, with a quarter-mile run of 13.0 seconds at 108 mph. That makes the GXP one of the quickest sedans in its price range. The GXP is powered by GM's LS3 V8, which also serves as the base engine in the Chevy Corvette. While the GT comes with a 6.0-liter engine, the GXP gets a 6.2-liter V8. The GXP is rated at 402 horsepower, 402 pound-feet of torque. The GXP also adds more performance goodies, including a standard limited-slip differential and 19-inch summer performance tires, and it's available with a six-speed manual transmission. Fuel economy is an EPA-estimated City/Highway 13/20 mpg, landing the GXP a federal Gas Guzzler Tax of $1,700, which you'll need to add to the price.
We like manual transmissions and the Tremec six-speed manual in the GXP shifts nicely. We grew tired of it around town, however. The relatively heavy clutch pedal and strong engine torque conspired to produce a jerky ride around town; it demanded attention and skill to drive smoothly and we weren't always in the mood for this. For around town use, we'd prefer the automatic.
Pontiac developed the GXP suspension on Germany's famous Nurburgring open-road race course. It's firmer than the GT suspension but we didn't find it harsh around town.
We used the brakes on the GT good and hard, and never reached a point were they got hot enough to start losing stopping power. The vented rotors are big, and they meet the high performance standard set by the engine, transmission and suspension.
The GXP offers larger rotors still, with lightweight aluminum calipers provided by Brembo. The advantages here are resistance to fade after repeated hard usage and more powerful braking to take advantage of the upgraded tires.
The Pontiac G8 succeeds with rear-wheel-drive performance, style, four doors and plenty of room. If the style, space and comfort is all you seek, the base G8 is a good choice, gets better fuel economy and runs on Regular gas. Our preference was for the GT model. We enjoyed its powerful V8. It handles well yet offers good ride quality. The GXP is fun, but not ideal for commuters in metro areas, especially with the manual gearbox.
Sam Moses filed this report to NewCarTestDrive.com after his test drive of the G8 models in Southern California. J.P. Vettraino contributed from Detroit. Editor Mitch McCullough drove the GXP model in Los Angeles.