RENNtech ECU HHT Upgrade for GL 550 X164 | 402 HP / 405 LB-FT audi-rs4--b7---2006-2008--4-2-v8-fsi-esr4648829 CL 65 (C216) Stock Performance:

CL 65 (C216) Stock Performance:

Fuel System Upgrade

Gains: +16HP & +19 LB-FT

offer a more responsive throttle and immediate power delivery thanks to a reduction in exhaust back pressure

Our down pipes mate perfectly with the stock Mercedes-Benz AMG exhaust system and include all necessary mounting hardware and clamps

RENNtech ECU HHT Upgrade for GL 550 X164 | 402 HP / 405 LB-FT audi-rs4--b7---2006-2008--4-2-v8-fsi-esr4648829 CL 65 (C216) Stock Performance:RENNtech ECU HHT Upgrade for 164 GL 550. Up to 402HP, 405LB FT. Gains: +20HP & 14LB FT RENNtech has been at the forefront of ECU tuning since electronic engine management started to show up in vehicles during the mid 1980's! Our experience, countless hours of in house research, development and exhaustive testing ensure that our proprietary ECU upgrade offers incredible performance gains and rock solid daily driver reliability. RENNtech tuning software