Stage 2 ECU Performance Engine Tune 4.2L V8/5V

The Unitronic Stage 2 ECU Performance Engine Tune is a sophisticated engine software upgrade engineered to unlock significant power from your VW or Audi's 4.2L V8/5V engine. It boosts output to 375 HP and 363 LB-FT of torque, a notable improvement over the stock 340 HP and 310 LB-FT. For 93 octane (98 RON) fuel, expect an additional +35 HP and +53 LB-FT. Unitronic has meticulously engineered this software with strict industry standards and conducted extensive testing across various driving conditions. Key features include the retention of factory safety limiters, removal of the speed governor, and precisely calibrated ignition timing for higher octane fuels. Drivers will experience optimized responsiveness, improved drivability, smoother power delivery throughout the entire power band, enhanced fuel efficiency, and elimination of lower-end hesitation or lag. This ECU tune requires an upgraded exhaust system to function optimally. It is compatible with the 2003-2009 Audi S4 4.2L V8/5V and the 2002-2003 Audi S6 4.2L V8/5V.