The R1 performance package for the Mercedes 55 series engine includes our proprietary ECU upgrade in addition to our full carbon fiber airbox upgrade which offers a larger volume of incoming air for better engine breathing and improved cylinder filling.

This combination that provides noticeable increases horsepower, torque and throttle response across the vehicles entire powerband while still maintaining daily driver reliability.  

R1 Performance Package includes:

• RENNtech ECU Upgrade
• RENNtech Full Carbon Fiber Airbox

SLK 55 (R171) Stock Performance:

• 355 HP @ 5750 RPM; 376 LB-FT @ 3500 RPM

Modified Performance:

• 385 HP @ 5500 RPM; 400 LB-FT @ 3000 RPM