ENGINE · 1988-2003
4G37 / 6A12 TT tuning
Mitsubishi 4G37 / 6A12 — Galant VR-4 / 3000GT VR-4 era platforms. I4 / V6 turbo / twin-turbo, 2.0 / 2.5 L, 195-280 HP (Galant VR-4 4G63T or 6A12TT) stock. Cars: Mitsubishi Galant VR-4 (E33A / EC5A), Lancer GSR Evolution I-III pre-4G63T variants, Eclipse 1G GS-T / GSX.
Engine specs
| Engine code | 4G37 / 6A12 TT |
|---|---|
| Configuration | I4 / V6 turbo / twin-turbo |
| Displacement | 2.0 / 2.5 L |
| Production years | 1988-2003 |
| Stock power | 195-280 HP (Galant VR-4 4G63T or 6A12TT) |
| ECU family | Mitsubishi 32-bit + EvoScan / ECUFlash → |
Tuning stages on 4G37 / 6A12 TT
| Stage 1 | +25-45 HP |
|---|---|
| Stage 2 | +50-100 HP (intake + downpipe + intercooler) |
| Stage 3 | +200+ HP (Garrett upgrade + fuel system) |
Conservative real-world estimates. Actual results depend on hardware health, fuel quality, ambient temperature, and the specific calibration written.
Services available on 4G37 / 6A12 TT
Common DTC codes on 4G37 / 6A12 TT
Brands running 4G37 / 6A12 TT
Workshop workflow
- Read the 4G37 / 6A12 TT ECU via OBD or bench using your existing flasher (KESS3, AutoTuner, MPPS, Trasdata, FRF).
- Open Softechpro V5 and drag the .bin / .ori / .hex / .s19 / .frf onto the workspace. The Mitsubishi 32-bit + EvoScan variant is auto-detected.
- Pick the service tab and apply Stage 1 / 2 / 3 / DPF OFF / EGR OFF / AdBlue OFF as required.
- Save patched .bin — the outer CRC is recomputed automatically.
- Flash via your existing flasher. Adaptation reset via OEM scan tool if required.