SAN DIEGO - Just in time for a summer of top-down cruising and long-haul family vacations, BMW AG introduces two new vehicles targeting completely different buyers but derived from the same vehicle - the venerable trendsetter, the 3-series.

Facing intense competition in a market it pioneered, the German automaker rolls out the 323Ci convertible and 323i sport wagon. Get used to the idea of model variants from BMW - the company will introduce 21 of them this year. A 3-series hatchback, for instance, is under consideration.

The convertible comes with a base price of $34,990, which is 10% less than the model it replaces, comparably equipped. It offers standard rollover protection, a glass rear window with electric defroster, seat-integrated seat belts and a body that is more rigid than the previous-generation 3-series sedan. When the top is up, a shelf inside the trunk collapses, offering an additional 4 cubic feet of space.

And when the top is up on a cool California morning, it's awfully hard to tell you're not in a hardtop, thanks to three layers of fabric protecting against the elements. The top is fully automatic - not unusual today - but the top clamps down on the header so tightly that you actually hear a "whoosh," from the release of air pressure. No wind noise here. And it's definitely quieter than the last-generation 3-series convertible.

BMW says it sold about 12,000 3-series convertibles in 1998, for 56% of the market. It sold the same amount in 1999, but its share declined to 39% because of stiff new competition from Volvo C70 and Mercedes CLK.

The sport wagon, new to the U.S., has a base price of $29,200, placing it in the middle of its competitors. Judging by the success of the all-wheel-drive wagons like the Subaru Outback and Audi A4 Avant quattro, BMW's AWD 3-series wagon could be popular when it arrives later this year. The Mercedes C-Class, new for MY '01, also could offer AWD, sources say.

Although the wagon looks bigger than the convertible, it's actually more than 200 lbs. (91 kg) lighter (and therefore a more spirited drive) because of the structural reinforcement necessary for rigidity in the convertible. In Europe, BMW demonstrated for journalists the strength of the convertible by balancing another convertible on top of its windshield, steadied only by guy wires.