The Austrian/Swiss tuners from O.CT were recently tasked with adding more power to the 4.2i V8 version Audi R8. Of course this could have been achieved in many ways, but their solution was to add a compressor with CNC mastered aluminium holding system to the engine, plus a custom suction system and an inner overflow-overpressure system.
The O.CT Audi R8 V8 also features a vent system for the crank case and a modified set of toothed belts, plus the engine has received a remapped ECU while the Vmax limiter was dropped.
Finally the German sports car has also received a stainless steel exhaust system and as a result the output has increased from 420 HP to 565 HP and 560 Nm of torque. The new performance figures are 0 to 60 mph in 0.7 seconds faster than the standard version  and from 0 to 155 mph in 24 seconds.

Source: O.CT TUNING