This is the problem: According to ATT Autotechnik -- the M3 Convertible is so good, why bother with any other 3 Series convertibles? And they have a point... until now! Meet ATT's new Doppleturbo-Cabriolet. What they've done is to take a regular BMW 335i convertible and make it quicker. How much quicker?
The regular 335i is rated at 300 horsepower and 300 pound-feet of torque (though, of course, those numbers are underrated a bit). The Doppleturbo on the other hand makes 356 hp and 388 lb-ft of torque. A little less power than the M3 (414 hp) but nearly 25% more torque (the M3 makes just 300 lb-ft). You also get a stainless steel exhaust and big, good looking 20-inch, 20-spoke wheels (though some more brakes would be nice, at least visually speaking). But is it any good?
Well, in the past we've seen BMW tuners do the whole less-horses-more-torques thing with good results. Anybody remember Alpina's take on the Z8? Essentially, rather than use the E39's high-strung 5.0-liter V8, Alpina bored out a 4.4-liter BMW V8 to 4.8-liters. The results were 375 hp (vs. 394 hp) and 383 lb-ft of twist (vs. 368 lb-ft) and according to all lucky enough to drive the car, a much preferable grand tourer to the "stock" car. Could ATT Autotechnik have worked the same magic with the Doppelturbo? Maybe. Awkwardly translated press release after the jump.