Autotechnik + Tuning or ATT has given the M3 Convertible a bit more fire under its belly. The car is already powerful with its standard 4.0-litre V8 pushing out 309kW (420hp). But in the tuning world enough is never enough.
By giving it a compressor system, optimising engine software and installing a new exhaust system with optimised dynamic pressure, ATT was able to extract an extra 59kW (80hp) to make it an even 500hp (368kW). For extra enjoyment the tailpipes were apparently tuned to give out two different sounds. ATT will do the engine job for €11,749 including installation.
Wheels fitted are 8,5x20 and 10x20 alloys while the matching tyres are Michelin Pilot Sport 2s measuring 245/30 ZR 20 and 285/25 ZR 20 front and rear respectively. Although generally praised as a very competent handler, ATT felt their M3 needed an extra dose of road-holding ability. So they included a KW coilover suspension system in the kit for about €2,000.
The interior can be ordered with a cabin largely made of carbon fibre or Swarovski crystals. ATT calls it the Thunderstorm M3 and with a name like that we cannot wait to see the performance figures.