M139 · W177

Mercedes-AMG A45 S W177 — M139 Tuning Guide

The most powerful production 4-cylinder ever made. Stage 1 cracks 480 hp.

Engine Overview

Displacement
2.0L I4
Stock power
416 hp
Stock torque
369 lb-ft
Induction
Single twin-scroll roller-bearing
Fuel
Direct + port injection
Redline
7,200 rpm

Stages & Expected Gains

StageHPTorqueRequirements
Stage 1+50–70 hp+50–80 lb-ft98 RON
Stage 2+90–120 hp+90–120 lb-ftDownpipe + intake
Stage 3+150+ hp+130+ lb-ftE50 + upgraded turbo

Recommended Mods

Stage 1
  • Stock
  • 98 RON / 93 octane
Stage 2
  • Catless downpipe
  • High-flow intake
  • DCT tune
Stage 3
  • Flex fuel
  • Upgraded turbo
  • Front-mount intercooler

Known Issues to Watch

Stock Turbo Limit

Roller-bearing single tops out around 550 hp. Past that, hybrid or full upgrade.

Heat Soak

Tiny engine bay — log IATs on track and consider auxiliary IC sprayer.

  • Stock turbo limit ~550 hp
  • Heat-soak on track

Compatible Platforms

VR TunedPosaidonWeistec

Ready to plan your W177?

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