Mercedes A45S AMG W177 MY2021 – #Etuners Stage2

In the battle for the most powerful 2-liter engine, Mercedes AMG clearly has the edge over its competition. Back in 2014 when it started producting the A45, it was by far the most powerful two liter engine at 360hp and then 380hp with its facelift version. Bringing it in direct competition with Audi’s RS3, which is 2.5 liters instead of just 2.

Shortly after 2017, rumours spread that other companies where trying to produce a more powerful engine to take part in the race. Before anyone could respond, AMG started producing the A45S, which at 420hp is the most powerful two liter engine in production. Its M139 engine also holds the record for the highest specific power at 210hp/liter.
Because of the addition of a particle filter in the exhaust, owners who upgraded from the A45 were not very happy with the exhaust sound. To fix this, an upgraded downpipe with a sports cat was installed to the car that came to us.

With the stock software and upgraded downpipe it made 432hp at 559Nm of torque. We developed a custom #Etuners Stage2 remap on dyno. Power increased to 510hp at 680Nm, making it even faster than it already was.

Upgrade specifications

  • 98RON fuel
  • Upgraded downpipe with sports cat
  • #Etuners Stage2 ECU remap

Performance results

  • Maximum engine power (measured in linked AWD): 510hp (measured stock with downpipe at 432hp), gains 78hp
  • Maximum engine torque (measured in linked AWD): 680Nm (measured stock with downpipe at 559Nm), gains 120Nm