Two imports tie in this year's search for the 'ideal' automobile

What's the best car in the whole wide world -- best for the money, that is, but not necessarily quality, amenities, and prestige?

To the Automobile Club of Southern California, it may be something as plebeian as a ''low cost'' import from Japan.

For the last eight years, the club has been testing cars in its perennial search for the ''ideal''car, one that carries at least four passengers and gives a good account of itself on the road.

The British-built Rolls-Royce carries four passengers all right, with all the amenities of home, but it wasn't even in the ball park.

The ''ideal'' top car this year -- or rather the top two cars - are the Mercedes-Benz 300SD, a turbocharged diesel with a $35,000 price tag and the front-drive Nissan Stanza with a base sticker tag of under $8,000. The two cars tied for top spot on the automobile club's scorecard.

The club has certain specific criteria to help it make its choice. For example, it computes the annual cost of maintaining a car, including the cost of the vehicle itself, taxes, shipping costs, depreciation, upkeep, and registration fees. Too, it figures that a new car is kept four years by the original owner -- a not-unrealistic assumption in today's down-at-the-heels marketplace.

All of this culminated in a ''cost per point'' -- in other words, the cost of owning and operating a vehicle for one year.

The organization figures in a bunch of other things as well, such as the fuel economy of the vehicle, how much room it provides the occupants, whether it can get out of its own way on the highway, how much luggage it can carry, the quality of the ride, the ease of getting in and out of the car, and the size overall outside.

In other words, what features are most important to most buyers in choosing a new car? That's the basis on which the scores are made.

The purpose, according to the club, is to influence carmakers to produce more vehicles that will seat -- comfortably, that is -- four adults, that perform with some degree of satisfaction to the owners of them, and that conserve resources to boot.

Import market that it is, the California motorists gave most of the top spots to the imports although the domestic makes gained somewhat this year from a less-than-enthusiastic showing a year ago.

The Cadillac Cimarron, for example, picked up 63 points ($51 per point) and the Buick Skylark 68 ($36 per point). The Chrysler LeBaron and Dodge Omni drove off with 61 points each ($44 and $35, respectively); and the Ford Escort and Chevrolet Chevette with 58 ($33 and $35). The AMC Concord had 59 points ($36 per point) and the Chrysler New Yorker 56 ($60).

As for the Mercedes 300SD and the Nissan Stanza -- the latter a midsize front-drive replacement for the old Datsun 510 -- they tied at 80 points apiece. Yet the cost-per-point ratings were a world apart. The top-of-the-mark West German car has a per-point cost of $93 while the much-lower-cost Japanese car is rated at $26. Next in the line was the Mercedes nonturbo diesel 300D with a score of 76 ($82).

The Nissan Stanza, in fact, was the lowest of the bunch -- a super-high score and a minuscule cost per point.

Not considered were such items as braking, styling, or emissions control.

Interestingly, the Lincoln Continental rated 53 points but the per-point cost checked out at $98, even higher than the Mercedes 300SD.

California is a bellwether of many trends, not the least of them automotive. If a dump truck makes a big-10 list of automotive ''must-haves,'' look for one in your neighborhood new-car dealership down the road.