Delivering reliable spark under massive twin-turbo boost pressure is vital when tuning the S63 engine for higher output. Prevent high-rpm misfires by refreshing your ignition system with Genuine BMW coil packs or heavy-duty Upgraded MMX Coil Packs designed specifically to handle extreme cylinder pressures. If you want a substantial, plug-and-play power increase without permanently altering your factory ECU software, install one of our RaceChip GTS5 Black Tuning Boxes, engineered to safely optimize sensor data for instant, reliable gains in horsepower and torque.