Product description: Audi TT 225 hp 1.8T performance upgrade to approx. 270 hp / 370 NmThe kit includes :- Stage 2 software tuning- Reinforced intake hose- Reinforced bypass valve- BMC High-Performance Sport Air Filter for 1.8TThe control unit must be sent to us, or you can schedule an appointment at our location. You must use at least 98 octane fuel!The following components are also required for Kit 2 to achieve the desired performance: Stainless Steel Exhaust System 70mm http://www.turbo-parts.de/Abgastechnik/Abgasanlagen/Audi/S3-8L-210/225PS/Auspuffanlage-fuer-Audi-S3-210-225PS-A3-Quattro-8L-o-70mm-Edelstahl-TUeV::1485.html1.8T TT 76mm Stainless Steel Downpipe with 200 CPI Racing Cat http://www.turbo-parts.de/Abgastechnik/Abgasanlagen/Audi/TT-225PS-8N/Auspuffanlage-fuer-Audi-TT-225PS-8N-Quattro-1-8T-o-70mm-Edelstahl-TUeV::1481.html