Accomplished Mercedes Benz tuner Renntech has played around with the already overpowered SL65 AMG Black Series, and has come up with a hardtop coupe that shoots out 865 horsepower and 1,000 pound-feet at the crank.

The Renntech SL65 Black Series dyno run had 5 more HP than the Brabus Vanish, which was clocked in at 800 HP. That’s also 135 more ponies and 263 more lb-ft than the stock SL 65 Black Series.

This car means business even next to SLRs Roadsters. The SL65 Black Series has the kind of threshold of power-to-weight-to-possible grip. Everybody would surely like to experience this kind of power. It is simply a monster HP/torque kind of vehicle.

The Renntech version gets an ECU revision, upgraded intercooler pumps and sport mufflers in a package that begins at $16,390, which when you look at the price tag of the actual SL65 Black Series at $250,000 is pocket change. That doesn’t include the transmission upgrade and LSD you’ll probably want to go along with it.