The American luxury-car tradition has never been afraid of generous dimensions, and in this sense the new Riviera is thoroughly in touch with its heritage. It's bigger than either the Eldorado or Mark VIII - bigger, in fact, than any luxury coupe this side of a Bentley Continental R.
But other elements of the traditional American luxury car - sluggish handling, vague steering, indifferent braking performance - are conspicuous by their absence. The Riviera shares a number of chassis components with the Oldsmobile Aurora - a chassis that is probably the most rigid in GM history, with the possible exception of the Chevrolet Corvette.
Chassis stiffness - a new religion in the domestic industry - is the key to durability, noise isolation and good handling. Even though the Riviera has no sports-car pretenses, it's devoid of the undignified wallowing that afflicted the American luxoboats of yesteryear.
Aside from some very minor trim changes - a little less chrome - the Riviera is visually unchanged from its triumphant introductory year.
There is a significant change under the hood, however. The original base engine - GM's 3800 V6 - has been replaced with an extensively re-engineered 3800 Series II edition, and it's a brilliant piece of work. The 3800 Series II has the virtues of its predecessor - manufacturing simplicity, quiet operation - in a package that's more compact, lighter, more fuel efficient and more powerful: 205 hp versus 170 hp.
The Riviera's upgrade engine continues to be a supercharged version of the old 3800 V6, appropriately called the supercharged 3800 V6.
Besides the supercharged engine, different wheels and speed-rated tires, there's not much distinction between a basic Riviera and an uplevel version, nor are there any specific model designations.
All models do share one flaw: the Riviera's elongated tail, which is the only element of the exterior design that seems exaggerated. It provides plenty of trunk space, but getting to its innermost regions requires an awkward stretch.
If nothing else, the new Riviera is roomy, front and rear. In fact, it has more rear-seat head- and legroom than a good many sedans, luxury and otherwise. There's real move-around space for four inside, and rear-seat access is relatively painless thanks to the extra-long doors.
You can also fit five passengers inside without too much elbow-rubbing, but we think the Riviera's 6-passenger configuration is one passenger too many.
Another pleasant interior surprise is the Riviera's elegantly understated dashboard design. As they did with the exterior, Buick's designers took some risks here. Instead of the usual collection of wood and chrome accents, the Riviera's dashboard is sweeping, clean and simple, with oversized instruments and secondary controls.
Our only criticism concerned the tachometer, with its lower left corner partially eclipsed by the steering wheel.
Consistent with the roomy interior, the Riviera's power-adjustable seats are spacious and well-shaped. Although our test car had bucket seats (instead of the 3-passenger front bench), there wasn't much in the way of side bolstering, but there was plenty of living-room comfort and adjustability.
Secondary controls are generally well-marked and well-located, though it would be helpful if the power-window switches, which are mounted on the driver's armrest, were backlit, as in the Aurora.
Standard equipment is plentiful: power windows, mirrors, front seats and antenna; AM/ FM/cassette sound system; remote keyless entry; dual zone automatic climate control; cruise control; power remote trunk release and a leather-wrapped steering wheel.
Besides its supercharged engine, our test car had leather upholstery, a CD player, a memory heated driver's seat and a Prestige Package that included traction control, a self-dimming inside mirror and power lumbar adjusters.
Safety equipment meets or exceeds 1997 federal passenger car standards and includes side-impact protection, dual airbags, disc brakes on all four wheels with anti-lock, adjustable upper seat-belt anchors and 5-mph bumpers.
Supercharged is a loaded word, because it tends to conjure up Ferrari-esque performance expectations. That's not what the Riviera's supercharged 3800 V6 is all about. It doesn't produce much more peak horsepower than the non-supercharged engine, but it does have a big edge in torque - the low-rpm thrust that gets you moving at stoplights and generates the extra hurry you need for passing.
Although we think the Riviera's standard engine provides enough power to satisfy most owners - remember, this isn't a sports car - the supercharged 3800 V6 does move this car's considerable bulk in a faster-than-ordinary hurry. We were also impressed by the smooth shifting of the 4-speed automatic transmission, an area where GM is one of the industry's leaders.
But even more impressive is the Riviera's blend of handling control and smooth ride quality. Although weight is the enemy of quick directional changes, the Riviera's mass is well-controlled. There's not much body roll in hard cornering, the steering is precise without being heavy and braking performance is excellent.
Getting that kind of control usually means sacrificing ride quality, but we think the chassis engineers have come up with a contemporary balance on this issue. The Riviera's ride is firmer than previous American luxury cars, but it still smooths out potholes and expansion joints without a trace of harshness.
We were also impressed by our test car's interior noise levels. The Lexus LS 400 is still the queen of diminished decibels, but the Riviera is definitely near the top of the chart.