RENNtech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal!
Our proprietary tuning module stores both the RENNtech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming takes only a few minutes and the vehicle can be reflashed at any time as many times as you wish.
RENNtech has been at the forefront of ECU tuning since electronic engine management started to show up in vehicles during the mid 1980s! 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 for Mercedes offers significant gains in horsepower and torque across the vehicle's entire power band. By modifying ignition timing and throttle mapping, optimizing air-to-fuel ratios, increasing the engine's rev limiter and modifying boost mapping for turbo-charged vehicles, RENNtech performance software unleashes the true potential of your Mercedes.
 
Notes:
We have found the M177 engine stock performance numbers vary from the baseline figures claimed by Mercedes-Benz. We typically see higher baseline numbers than claimed by the factory.
Power gains are calculated based on stock numbers measured by RENNtech. Crank Performance Numbers are calculated with a 14% Drivetrain loss on 4MATIC+ vehicles.
Numbers published by MBUSA are an average over a 750rpm range for HP and a 2,000rpm range for TQ. Power gains are calculated b