Just when BMW had reduced the price of admission, it has increased the distance to an impossible dream.

For a year, aspirants to better things in motoring have been content with the entry-level BMW 318i. It costs only $19,900, is powered by a modest 4-cylinder engine, but offers the full satisfaction and snootiness of owning any Bimmer.

Now Bayerische Motoren Werkes is introducing the BMW 850i to America. Suddenly, owning anything else in a BMW clearly is posturing. Drivers, start your salivating.

The 850i is fitted with a V-12 engine so powerful that even when shaking its booties on Germany's Autobahnen, top speed is judiciously and electronically regulated to 155 m.p.h. That V-12 engine--a sophisticated configuration shared with such notables as Jaguar, Honda's Formula One cars and the P-51 Mustang--delivers 296 horsepower and a zero to 60-m.p.h time of 6.8 seconds.

Those are Ferrari and Porsche numbers.

So is the price. The 850i in base form costs $73,600. Add the double bummers of gas guzzler and luxury taxes and the sticker bloats to $80,000.

But at the risk of alienating all those living memorials who can remember when $80,000 bought a three-bedroom house in Santa Monica, the 850i is well worth whatever piece of real estate you might have to sell to get one.

It is a new design from grille to trunk latch and arguably BMW's prettiest car since . . . um, well, how about the 1937 Type 328 drophead coupe? The engine and suspension technology is a battery of thinking electronics that automate safety and adjust driving dynamics until even in rain, on black ice or thick oatmeal, the only duty left to a driver is steering around hard objects.

Although originally intended to replace the successful and very attractive 635CSi coupe, the 850i actually has overstepped that place in line to move alongside the 750iL sedan as a flagship of BMW's fleet.

The new shape and slippery looksare good enough to crush anything else at a Miss Bavaria pageant. The hood is longer, lower and flatter and slopes softly to an almost miniaturized front end. BMW's hallmark kidney-shaped grilles now look no larger than a couple of navy beans. Headlights, for the first time in BMW's history, have gone pop-up.

There's a wedge profile to the car that has been emphasized by moving the cab closer to the rear. There it flows into an abbreviated, high trunk barely short of squat.

The side glass is another piece of magic. One second after driver or passenger doors close, windows automatically slip up an inch to snug themselves into the roof frames. It makes for a flush finish, zero wind noise in the cabin, and total aerodynamic hygiene.

Internally--from a steering wheel that adjusts for rake and reach to seats that are more comfortable than 15-year-old Levis--the 850i is flawless.

Front seats are the popular twin-pod configuration with a fully functional center console as the divider. It holds the hand brake, gearshift, radio, heater, CD, telephone, power window, side mirror and other controls and all seemingly clustered beneath a single hand span.

Rear seats are a little larger than most indentations found in the back of modern 2+2 coupes. But even for young teens it's a bit of a squeeze and a wriggle to get there.

Driver's-side air bag, of course. Instruments are a gas gauge, a tachometer, speedometer and engine temperature, all analog and with everything simple for clarity of function. Because at 150 m.p.h., eyes have no time to scan small dials for digital dots in several colors.

A pleasant touch to these splendid living quarters of soft leather and carpets thick enough to bury your fingertips: a small, rechargeable flashlight plugged into a socket inside the glove box.

One touch? Actually, little luxuries abound in the 850i. On its 12-speaker sound system (with a 6-disc cartridge in the trunk you hear fingers scuff guitar strings. Squirts from the windshield washer are followed by three quick passes from the wiper blades . . . halt, pause, then one last sweep to catch final dribbles. And at night there's a rear view mirror whose degree of dimming is decided by the brilliance of the following headlamps.

The 850i is a grand tourer.

Its express purpose is the secure munching of 500 road miles in exactly five hours with no great taxing of the human frame or brain. That role was demonstrated without argument by a day of high-speed running and maneuvering at Willow Springs Raceway, at Rosamond, north of Lancaster.

We were in rich company and all of it from Germany.

On the track was a 200-m.p.h. Porsche 959 supercar, the first to be legally imported to the United States. In the pits was a Porsche 917K, a 1969 veteran of Le Mans, the race in France, and "Le Mans," the Steve McQueen movie. Alongside was a 750-horsepower, twin-turbo Porsche 935 that ran endurance races at Riverside International Raceway in the late '70s.

All were on an exercise pass from the Vintage Museum of Transportation and Wildlife at Oxnard, blowing out the kinks and cobwebs of permanent exhibition while thundering their stuff for a cable television crew.

We did not attempt to stay with this pride of Porsches.

On the other hand, none of the tough guys were capable of touching 130 m.p.h. on the pit straight with the climate control set to early summer, the Alliance Hall Dixieland Band playing "Clarinet Marmalade" on the CD and the driver taking a phone call.

At such speeds, the 850i impresses as an example of smooth and enormous power controlled by systems with capabilities to spare at any level of driving extremes.

The brakes are 13-inch discs on all four wheels and if applied at speed, the only drama and dive is performed by the driver accelerating forward against the shoulder strap.

The steeringis power-assisted, absolutely free of mush, with never any doubt as to where front wheels are pointing or how hard they are working around a corner.

Although the V12 with a four-speed automatic transmission doesn't deliver enough initial torque to set the car leaping off the line from rest, acceleration is magnificent in the intermediate to high-speed ranges.

The engine doesn't rumble and snort like a Ferrari. Power doesn't kick the kidneys like a Turbo Porsche. The effect is simply that of a purposeful surge of sustained, smooth, rising, very refined horsepower from enough cylinders and pistons to spread the load around until the whole really seems to be loafing.

There's a new, multi-link rear suspension on the 850i. The patented system prevents any change in the set and geometry of the rear wheels under the forces of cornering, braking or acceleration. It also establishes a "toe-in" of the rear tires that further assists the balance of the car during sh arp cornering maneuvers.

Finally, there is ASC--which stands for Automatic Stability Control and which means a little more of a driver's quick thinking in adverse conditions is done for him.

With ASC, sensors that serve the car's anti-lock brake system also monitor incipient wheel spin. When a driving wheel slips, they order the engine to reduce power to that rear wheel and a skid is avoided.

Yeah, right.

So we tried it, and violently, by stomping on the power after hard cornering through a fast bend.

The right rear began to slip, the car was looking to slide . . . but despite the heavy foot on the gas, engine power came off until the wheel stopped slipping and cornering resumed.

A car that decides its own power settings, of course, is not the ideal vehicle for negotiating a race track in any kind of a hurry. But the 850i wasn't designed for race tracks. It was built to travel far and fast with mechanical and electronic skills that wi l compensate for the inattentions of average drivers.

All of which makes the BMW 850i a class act.

Definitely world class.

1991 BMW 850i

The Good Smooth, refined, enormous power. Smooth, refined, enormous braking. Enough technology to forgive driving misdeeds. Best-looking Bimmer. Top-quality appointments.

The Bad Not being able to afford one.

The Ugly Optional forged alloy wheels--and at $1,000 a set.

Cost Base, $73,600. As tested, $77,600 (includes leather power seats, automatic transmission, driver's side air bag, anti-lock brakes, automatic climate control, sunroof, 12-speaker sound system with CD player, cellular phone and gas guzzler tax.)

Engine 5-liter V-12 developing 296 horsepower.

Type Rear-drive, 2+2, high performance sports coupe.

Performance 0-60 m.p.h., as tested, with automatic transmission, 7.4 seconds. Top speed, 155 m.p.h. Fuel consumption, as tested, city-highway average, 17 m.p.g.

Curb Weight 4,123 pounds.