Full Flex Fuel Add-on

Unlock the true potential of your WRX with full flex fuel tuning — now with lifetime support.
This add-on enables real-time ethanol-based tuning using our custom-built flex fuel feature. Your engine will automatically adapt fueling, timing, and boost targets based on the ethanol content in your tank — from 93 to full E85 and everything in between. No manual switching. No reflashes. Just seamless performance.
 
What’s included:
– Real-time fuel adjustment based on ethanol content
– Custom logic by M77 Performance for smooth transitions
– Lifetime update support
– No map switching needed after setup
 
Requirements:
– A working flex fuel sensor
– An M77 Performance E-Tune (sold separately or bundled)
Add this to your tune and enjoy a dynamic, worry-free driving experience — no matter what fuel you run.
 
Important Disclaimer:
This tune add-on is for off-road/motorsports use only. By purchasing, you acknowledge:
– You are responsible for your vehicle’s mechanical condition and emissions compliance.
– M77 Performance assumes no liability for damage, misuse, or legal issues.
– You must agree to our full Terms of Service during checkout.