Unitronic Stage 2 Performance Engine Tune For VW/Audi 4.2L V8/5V 

Performance Software Precisely Engineered to Run with a Upgraded Exhaust System

Power Gains: 375 HP / 363 LB-FT (Stock Power: 340 HP / 310 LB-FT)

• 93 Octane / 98 RON GAS: +35 HP / +53 LB-FT

Features: 

• Engineered with Strict Industry Standards
• Extensively Tested Under Various Driving Conditions
• Factory Safety Limiters Retained
• Optimized Responsiveness and Drivability
• Optimized Smoothness and Driving Comfort
• Power Delivery Perfectly Optimized Throughout the Power Band
• Improved Fuel Efficiency
• Speed Governor Removed
• Lower End Hesitation (Lag) Removed
• Ignition Timing Precisely Calibrated for Higher Octane Fuel
• Precisely Calibrated for an Upgraded Exhaust System
• Optimized for a High Flow Catalytic Converter

Required Hardware: 

• Upgraded Exhaust System

Fitment: 

2003-2009 Audi S4 4.2L V8/5V

2002-2003 Audi S6 4.2L V8/5V