The economy may be in the doldrums now, but when it straightens out, many automakers will be in a position to cash in with what is the best lineup of luxury cars ever offered. Japanese automakers -- Acura, Lexus and Infiniti -- have led the way with one new model after another. Mercedes-Benz, with seven new models, leads the charge from Europe. Here's a look at what's new with 1992's luxury and full-size cars: ACURA: Legend-- Introduced earlier this year as 1992 models, the coupe and sedan carry on with no changes. Coupe base price: $30,900; sedan base price: $35,500. Vigor: The midsize five-cylinder Vigor, also introduced earlier this year, is unchanged. Base price: $23,265. ALFA ROMEO: 164-- Again three models are offered, the base model, the luxury model and the sports model. New colors are the only changes. Base price: $25,865. AUDI: 100-- Three new models here have been restyled. The old five-cylinder has been replaced by a more powerful V-6. There is more room on the inside, and the new cars, 100, 100S and 100CS, are bigger, wider and better-equipped than last year's models. Base price: $27,700. BMW: 3-Series-- The 325i sedan was introduced earlier this year and carries on with no changes. The old 325 continues in coupe and convertible form until the new one arrives sometime next year. Base price: $27,990. 5-Series: Minor changes only. Base price: $35,600. 7-Series: No major changes. Base price: $52,990. 850i: The V-12 sports coupe has some minor suspension enhancements but is basically unchanged. Base price: not available. JAGUAR: XJ6-- No changes in this classic British luxury sedan. Base price: $44,500. XJS: It may take a second look to notice the changes, but Jaguar's sports coupe has been given a thorough overhaul. Though the looks are still close to the same as last year's model, the '92s are lighter and more aerodynamic. Under the hood, the silky-smooth V-12 has been given a power increase. A convertible is again available. Base price, coupe: $60,500; convertible, $67,500. MAZDA: 929-- The square old 929 is gone. In its place this year is a smooth, aerodynamic beauty that is aimed at the mid level luxury market. Power comes from a 195-horsepower, 24-valve V-6 and an electronic four-speed transmission. There is a leather interior available as well as a CD player, electric sunroof, a long list of power accessories and everything else you could want in a midsized luxury car. Base price: $27,800. MERCEDES-BENZ: S-Class-- This could be an interesting year for Mercedes. The German company has rolled out a new series of five S-Class sedans. There is one turbocharged diesel model, one six-cylinder, two V-8s and a V-12 available. The 300SE, 300SD and 400SE are all the same size but differ mechanically. The 500SEL is a bit bigger, while the 600SEL is Mercedes' new flagship. Prices range from $69,400 to $127,800. 400E/500E: These are two new V-8-powered midsize sedans that, with prices starting at $55,900, are aimed squarely at the competition. They are not as fully equipped as the S-Class cars, but still come with a long list of standard features. The 500E is a limited-edition sports sedan. NISSAN: Infiniti Q45-- The much-needed chrome grille still is available for Japan-only models. In fact, there are no styling changes for Nissan's high-performance luxury/sports sedan. Only the electronic door-lock system has been changed. A small "a" appears on the rear flanks on cars equipped with the optional full-active suspension package. Base price: $42,000. Infiniti M30: The M30 also carries the same door-locking system installed on the Q45. Other than the locks, no changes have been made. The M30 again is available as a convertible. Base price: $25,000. Infiniti G20: Also gets a revised electric door-locking system, but that's about it for Infiniti's best-selling car. Base price: $18,300. SAAB: 9000-- No styling changes, but there are significant mechanical and equipment upgrades for '92. The body is stiffer on all models, and side-impact beams have been added near the door sills. On turbocharged models, traction control is now standard. A special limited production 9000 called the Griffen will be available later in the model year. Base price: $24,845. 900: Better tires and a 150-watt stereo are all that is new here. Base price $19,395. TOYOTA: Lexus LS 400-- The Lexus flagship rolls into 1992 sporting nothing new other than its higher price. Base price: $42,200. Lexus SC 400: Introduced earlier this year as a 1992 model, this car is sold out until sometime after the first of the year. Base price: $37,500. Lexus SC 300: The SC 300 shares the same body as the SC 400, but it has a different drivetrain and lower price. The SC 300 features a straight six and a five-speed manual gearbox. Base price: $31,100. Lexus ES 300: The ES 250, a thinly disguised Camry, is gone. The new car is bigger and more powerful than the ES 250, and it shares some of the LS 400's styling cues. It is powered by a 185-horsepower, twin cam V-6 and can be had with either a manual or automatic transmission. Prices start at $25,250.