RennTech ECU+ Upgrade 2019-2023 Mercedes-AMG GT 63 S 4-Door X290

The X290 AMG GT 63 S 4-Door is already a heavy hitter, but RennTech found real headroom in the M177 twin-turbo V8. On its own dyno RennTech measured the car at a peak 681 hp and 736 lb-ft stock, and the ECU+ calibration raises that to 783 hp and 798 lb-ft at the crank. The result is +102 hp and +62 lb-ft, and unlike most tunes at this level it carries a CARB Executive Order, so it is street legal in all 50 states.

See how the RennTech HHT works

Features

• 50-state street legal: RennTech holds a CARB Executive Order for the HHT on M176/M177/M178 4.0L V8 engines
• Flashed through the OBD2 port with the RennTech HHT, no ECU removal
• Your factory file stays stored in the HHT so the car can go back to stock at any time
• Ignition, throttle, fueling, boost and rev-limit mapping revised for this chassis and engine
• Developed and tested in-house by RennTech for daily-driver reliability

What is included

• RennTech HHT hand-held tuner with the X290 GT 63 ECU+ calibration
• OBD2 connection to the vehicle

Specs

Fitment notes

For the 2019-2023 X290 AMG GT 63 and GT 63 S 4-Door Coupe. Not for the GT 43 / GT 53 4-Door (M256) or the two-door C190 / C192 AMG GT. Crank figures use RennTech's 14% drivetrain-loss factor for 4MATIC+ cars, and 93+ octane is mandatory. RennTech offers a lower-power file for areas with poor fuel. Your VIN is required with the order.

Fitment