GLA45S H247 — Stage 1 Remap

The M139 motor in the GLA45S responds well to software-only tuning, and this Stage 1 file demonstrates exactly that. Power climbed from 255 kW to 309 kW at the wheels, with torque lifting from 456 Nm to 502 Nm. All of this came from ECU calibration alone, no supporting hardware required.

The customer wanted more usable mid-range punch without touching the factory setup, and the calibration delivered. Torque spread is broader through the middle of the rev range, throttle response sharpens up noticeably, and the gearbox programming integrates cleanly with the revised torque limits.

This is a straightforward remap for street use on 98 RON. The factory drivetrain handles the extra output without drama, and the tune leaves headroom for future bolt-ons if the customer goes that route later.