2015-2021 WRX Flex Fuel E-Tune

2015-2021 WRX Flex Fuel E-Tune


This product is for cars with stage 2 or 2+ mods plus a Flex Fuel Kit and Upgraded Fuel Pump.

Get your 2015-2021 WRX a custom E-Tune from JM Auto. With a Flex Fuel E-Tune you get stage 2  or  2+ peak power increases of 29-38% HP and 20-26% FtLb TQ. On ethanol (E60) you also will see an additional power increase of 20+% and torque increase of 10+% over the stage 2 pump gas levels. That ends up being an impressive 70+% increase in power and 40+% increase in torque over stock! Check out our Ethanol Calculator for help blending your fuels (pump gas and E85) when fueling your car at the gas station.

Recommend Mods





Flex Kit

Fuel Pump

Once purchased we will send you a confirmation email with a link to our online pre-tune form. With the pre-tune form we make sure you have all the correct modifications to meet your power goals. Once filled out we will email you to get the E-Tuning process started.

By purchasing this product, you acknowledge that this is a digital file sent via email, so there are no refunds and no warranties. You have also read How E-Tunes Work and have gone over the Pre-Tune Checklist.



We are glad to provide custom E-Tunes for the 2015-2021 WRX based on our years of dyno tuning knowledge. With all the different performance part combinations, a one size fits all staged tune isn’t always the right choice. We take into account all the modifications you have along with your goals/expiations to give you the best driving/performing car. We also know the limits of these engines and know where in the engine rpms it’s safe to push them and where it’s not.

All of our E-Tunes utilize the latest Cobb Custom Features (CCF) maps to give you the best driving experience. Some of the features we set up on all tunes are:

  • Remove the stock “rev hang”
  • Full time closed loop fuelingWe tune every car with full-time closed loop fueling. That means the front O2 sensor controls the AFR under full throttle ensuring the AFR is always spot on.
  • Smoother boost for more linear power delivery
  • Boost by GearAll MT tunes have boost by gear. This helps your car hit close to boost target in all gears.
  • High Gear Over-Boost ProtectionWe employ over-boost protection in 4th-6th to limit boost below defined rpms. An example is if someone goes WOT in too high a gear at too low an rpm, boost is limited to wastegate pressure to keep engine loads low and reduce the risk of engine damage.
  • User adjustable Launch Control and Flat Foot Shift


If you have any questions about E-Tuning you can call us at 763-316-5882 or email us at