Weistec W.3 Turbo Upgrade, M178



Please contact tuning@weistec.com to see if a tune is available for these turbos on your specific application. Core exchange required.


The Weistec M178 W.3 Turbo Upgrade unlocks the true potential of the 4.0L Biturbo engine.  Power gains are substantial, especially in the top end.

The factory turbocharges are disassembled and fully inspected.  The compressor cover and center cartridge are then machined to accept our 5-axis CNC machined 65mm impeller wheel.  Externally, no changes are made to maintain a completely stock appearance.  The new impeller wheel supports greater power levels than the factory unit with little to no sacrifice in spool and response.  The turbochargers are then reassembled with new seals and fully balanced for smooth operation and OEM service life.  All the original oil and coolant lines bolt right up making for a simple install.

For maximum results, the combination of our Weistec Downpipes, and Weistec High Flow Air Filters is recommended.  A Weistec W.3 Turbo Specific ECU Upgrade is recommened.

Weistec W.3 Power Package AMG GT-S

Key Features:

  • Signifigant Horsepower Increase

  • 5 Axis CNC Machined

  • High RPM Balanced for perfect operation

  • Substantial power throughout the RPM range

  • Rev Limit increased to 7500 RPM (on compatible models with tuning)

  • Stock Appearance when installed

  • 100% Bolt on installation







  • POWER GAINS: + 309 HP