2008 Pontiac Grand Prix Performance
The Grand Prix's powerful performance is its best attribute. Although the sedan's engine is not the strongest or the most refined in the class, most testers like the performance. Car and Driver writes, "Some other sporty sedans can match this car's test-track accel numbers, but none of them can match its massive punch in urban close combat."
However, several note issues of refinement. The New York Times says, "Step on the gas too hard (it doesn't feel too hard) and the front tires squeal like pigs under a gate. Then the traction control kicks in, smothering engine power. The car bogs down. It's ugly." Edmunds finds "on twistier thoroughfares, the 2008 Pontiac Grand Prix feels larger than most of its competitors."
Acceleration and Power
The 2008 Pontiac Grand Prix comes with either a 3.8-liter V6 with 200 horsepower or, in its GXP model, a 5.2-liter V8 engine with 303 horsepower. Both models are front-wheel drive and both come with a four-speed automatic, though the V8 has an optional manual-shift mode. U.S. News' Rick Newman comments, "I was surprised, in fact, at the Grand Prix's pep. It seemed to be able to keep up with virtually any car in its class, and then some."
Many reviewers noted the muscle-car like acceleration of the Grand Prix, especially the GXP trim style. Car and Driver says. "Tramp on the gas, and the GXP rumbles to 60 mph in 5.7 seconds ... that time would have been second quickest in the all-star sedan field...and the GXP's quarter-mile time -- 14.3 seconds at 98 mph -- would have ranked with the best of that bunch." But, for some, that was too much. As a reviewer at the Detroit News puts it, "This high-performance edition of the Grand Prix reminded me of our old dog Cokie. When I used to walk him, he pulled me so hard in different directions that people passing by would often comment that I looked like I was water-skiing. In other words, there was just too much power and torque on his motor for my small frame."
According to EPA, the 2008 Pontiac Grand Prix gets 18 miles per gallon in the city and 28 on the highway when paired with its standard four-speed automatic transmission. The GXT gets 16 miles per gallon in the city and 25 on the highway.
Handling and Braking
The Pontiac Grand Prix's handling gets mixed reviews, with some impressed at the car's agility, but others disappointed in its lack of stability. Edmunds says, "On twistier thoroughfares, the 2008 Pontiac Grand Prix feels larger than most of its competitors, which is perhaps not much of a surprise when you consider that it's almost 10 inches longer than the Toyota Camry. In its favor, though, the Grand Prix is still fairly tight and tossable for a front-wheel-drive car." The Detroit News finds the Grand Prix "handled beautifully, especially on curvy roads in the foothills north of Phoenix. I never felt like I was fighting for control of the steering wheel or overwhelmed by muscle."
The New York Times reports, "When it comes to understeer, a little goes a long way, and the Grand Prix goes round the bend. Under acceleration, the car's weight shifts ponderously rearward, lightening the load on the front tires and provoking them to spin. This is especially bothersome while cornering." Meanwhile, U.S. News' Rick Newman says "notable body roll in spirited driving situations."
The Pontiac Grand Prix's braking is adequate. Car and Driver notes "braking performance -- 174 feet from 70 mph, and zero fade -- is on par for this class." And Consumer Guide finds "brakes on the test cars felt numb, spongy, but stopped well."
The GXP model of the 2008 Pontiac Grand Prix features an optional manual shift mode, known as TAP shifting. Road and Track says the system is easy to use perhaps because it was "inspired by the design of Shimano bicycle gearshift levers" though some reviewers lamented that there were only four speeds. Others reviewers note that the system does regulate the driver to some extent. As USA Today reports, "An engine governor prevents over-revving if you forget to upshift, or try to downshift when the car's going too fast for the gear you want. An annoying 'bong' tells you to try again later, stupid, when you're not on the verge of blowing the engine."