Mercedes-Benz has approved the S600-based Ocean Drive for production in the 2011 model year. But it won't be the only four-door convertible on the market. An Audi A7 cabriolet will hit the European market in early 2011, not 2009 as reported elsewhere.
The two cars will not be direct competitors. The Ocean Drive concept, unveiled at the North American International Auto Show at Detroit last January, is based on the Mercedes S600, a sedan with a 510-horsepower, 5.5-liter V-12 and a price tag starting in the $120,000s.
The A7 sedan will arrive before the convertible in the 2009 model year as a CLS-Class competitor, a so-called “four-door sport coupe.” It should sticker for much less than the S-Class. The A7 will be built on Audi's transmission-forward layout introduced in the A5 and S5.
The last four-door convertible of any volume sold in the United States was the 1961-1967 Lincoln Continental. It weighed about three tons and suffered significant body flex. The Ocean Drive and A7 cabrio will no doubt weigh a lot, but each will be based on an already stiff, substantial chassis and should be easier to build well than, say, the 300 convertible Chrysler was working on a couple years ago, following the ASC Helios.
And Mercedes and Audi have engines designed to move already heavy cars. The Ocean Drive could work with anything from the S-Class's 382-horsepower, 5.5-liter V-8 and 510-horsepower, 5.5-liter V-12 (in the concept) to the 525-horsepower, 6.2-liter AMG V-8 and 604-horsepower bi-turbo V-12. For the A7 cabrio, expect the 340-horsepower, 4.2-liter V-8, the 450-horsepower, 6.0-liter V-12, and the 450-horsepower, 5.2-liter FSI V-10.
