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ESS E-Flash S85 ECU Tuning Software

Regular price $895.00 USD
Regular price Sale price $895.00 USD

ESS E-Flash MSS65 ECU software is a result of extensive testing and exact calibration of ECU parameters to allow increased performance on either a stock car or in combination with other modifications. The ESS MSS65 S85 software is developed and tested in extreme heat in the Arizona desert as well as extreme cold temperatures in Scandinavia. The end user can select between tuned and stock software versions simply using the E-Flash system to load whatever version is required. Any future updates or changes in modifications can easily be accommodated through an emailed update. ESS E-Flash also includes full engine diagnostic functionality and code clearing capabilities.


  • 8400RPM limit, higher available as custom order
  • Removed top speed governor
  • Reprogrammed torque management
  • Reprogrammed throttle response
  • Reprogrammed ignition, VANOS, and fuel parameters for optimum operation

The software is compatible with performance cat-back exhaust systems. Header software available upon request. Catless compatible software is not available for customers from California.

This system can be used to program between stock and tuned, and it can also be used to load custom files/race fuel files/updates received from ESS over email.

The ESS E-Flash system can also be used to load software for ESS supercharger systems should you ever decide to upgrade to one of these.

Software available for both US and European specification cars.

Typical performance increase is 10-15WHP and 10-15ft/lbs of torque on 91AKI with software alone. 93AKI version will under normal conditions develop 15-20WHP and 15-20ft/lbs of torque.

Application intended for: E60 M5, E61 M5 from 2005 2006 2007 2008 2009 2010 2011