Who said American automakers are incapable of building exciting passenger cars? The recently tested 2006 Pontiac G6 GTP Convertible certainly doesn't lack for excitement.

The car's sleek body came dressed in bright "Crimson Red" paint, and the power, retractable hardtop retreated into the vehicle's rear section with a highly entertaining show that lasts about 30 seconds.

On the roll, the GTP Convertible was decidedly feisty with its 3.9-liter, 240-horsepower V-6 sprinting up inclines and whipping through high-speed corners with nimble confidence. The droptop demonstrated more stability than one expects in a front-drive car. Nice job, Pontiac. Excitement, indeed!

Now is about the time the anti-American-car contingent chimes in with the expected litany: "It's not a (insert favorite high-end foreign make here) ... The retractable hardtop and other major components will probably fail early in ownership ... If General Motors really believes in its new cars, why doesn't it offer generous warranties to match?"

OK, all these gripes might have some merit, but I'm turning a deaf ear after spending a week in a sporty, American-made car that I sincerely enjoyed.

As I mentioned, the G6 GTP Convertible looks good. It has smooth lines, but they're clean enough that you're not slapped in the face with an overly aggressive attempt to look hot.

The sharply inclined windshield is arguably the vehicle's most noticeable feature at first glance.

The tested car's 18-inch tires did not look oversized on a body only 189 inches long; dual, chrome-tipped exhausts were positioned just right, at the extreme edges of the car's tail end.

Inside, the look is likewise sporty, but uncomplicated. Large, round gauges behind the steering wheel are old-school cool and easy to read.

The center stack has large, easy-to-use buttons to control the climate and the eight-speaker Monsoon sound system.

A touring suspension and GM's "Stabilitrak" stability control system probably contributed to the tester's sure-footedness on curves and slalom runs.

Even at high speed, road and engine noises drifting into the cockpit were not enough to disrupt conversations.

The retractable roof was a pleasure to watch; on the tested G6 GTP, it sealed tightly when I asked it to close with the push of a button.

I was warned not to open or close the hardtop with the engine off as it could risk draining the battery. That was an ominous warning, but I'm one of those cowards who always keeps the engine on while triggering a powered convertible top. It's a small price to pay to be safe.

The tester was billed as a four-seater, but like most small convertibles, the rear-seat room is woeful, at best. Please don't put two human beings through that cramped experience.

And if you plan on a day of top-down motoring with one other person -- be it spouse, offspring or friend -- plan on bringing your wallet ... and little else. Pontiac lists a cargo capacity of 1.8 cubic feet with the top folded neatly back in the G6 GTP Convertible.

Well, at least they were honest about it! With the top up, cargo capacity is a still-tiny 5.8 cubic feet, according to Pontiac.

With the robust 3.9-liter V-6, fuel mileage is advertised at a tepid 18 miles per gallon in city driving and 26 mpg on the highway. However, Pontiac said regular unleaded gas is sufficient to do the job.

While the package of standard features on the tester was relatively lengthy -- including power exterior mirrors, power windows, cruise control and the aforementioned stability control system -- I thought the starting price of $29,365 for a small, non-luxury four-seater was a bit high.

Side-impact air bags in the front cost an extra $295. I could do without the optional leather package ($1,265); ditto the $190 system that enables you to start the car outside the vehicle.

The latter feature can be entertaining, but the thrill wears off quickly.

The same can't be said of the G6 GTP Convertible. It's excitement for the long run and a nice addition to Pontiac's stable. It shapes up as a fun car for young motorists and an equally fun second car for families whose primary vehicle might be a full-size sedan or sport-utility vehicle.

Pontiac G6 GTP Convertible at a glance Make/model: 2006 Pontiac G6 GTP Convertible Vehicle type: Four-passenger, two-door, front-drive, hardtop convertible Base price: $29,365 (as tested, $31,740) Engine: 3.9-liter V-6 with 240 horsepower at 6,000 revolutions per minute and 240 foot-pounds of torque at 2,800 rpm EPA fuel economy: 18 miles per gallon city; 26 mpg highway (regular unleaded) Transmission: Four-speed automatic with overdrive Steering: Power-assisted rack and pinion Brakes: Power-assisted, four-wheel discs (vented on front), with anti-lock Suspension: Independent, MacPherson strut-type on front; independent, multi-link on rear (stabilizer bars front and rear) Fuel tank: 16.4 gallons Passenger volume: 85.3 cubic feet Maximum cargo volume: 5.8 cubic feet Curb weight: 3,428 pounds Height: 57 inches Length: 189 inches Wheelbase: 112.3 inches Width: 70.6 inches Track: 59.8 inches on front; 60.4 inches on rear Ground clearance: 80.4 inches Tires: P225/50R18 touring radials Final assembly point: Lake Orion, Mich.

About the writer: The Bee's Mark Glover can be reached at (916) 321-1184 or mglover@sacbee.com.