E85 and Blender Pump Flex Fuel Conversion Kits

Flex-Box Smart BoxThe Flex Box allows you to operate your vehicle on any combination of ethanol and gasoline such as E85 (85% ethanol, 15% gasoline), E50, E20, E15, E10 or pure gasoline.

EPA-Certified Kits are available for Ford, Lincoln, Dodge and Chrysler passenger car and light truck models equipped with 5.7L Hemi motors, including Charger, Magnum, Chrysler 300, Dodge Ram and Durango. Fleet customers, please call (847) 518-5276 or write info@flexfuelus.com for details.

The Flex Box Smart Kit is available right now for Ford passenger car and light truck models equipped with 4.6L and 5.4L motors, including Crown Victoria, Lincoln Town Car, Mustang, F150, Navigator and Expedition.

07 – 05 Dodge Magnum, 5.7L V-8, Flex Box Smart Kit

Flex Fuel’s Flex Box for the 2007 – 2005 Dodge Magnum, 5.7L V-8, Flex Box Smart Kit

4.6L V-8, Flex Box Smart Kit

Flex Fuel’s Flex Box for vehicles with 4.6L V-8 engines including

  • Lincoln Continental (2002-1997)
  • Lincoln Town Car (2007-1997)
  • Ford Crown Victoria (2007-1996)
  • Ford Econoline E-150 1/2 Ton (2007-1997)
  • Ford Econoline E-250 3/4 Ton
  • Ford Expedition (2004-1996)
  • Ford Explorer (2004-2007)
  • Ford F-150 3/4 Ton Pickup (2007-1997)
  • Mercury Grand Marquis (2007-1997)
  • Mercury Mountaineer (2007-2004)
  • Mustang V-8 w SOHC (2004-1997)

How it Works

To meet all of the requirements to achieve EPA certification and to maintain the original manufacturer warranty, a supplemental fuel injection system was required.

  • Fuel injection engines need additional fuel when alcohol is introduced.  Gasoline powered vehicles are not calibrated to sense or add the needed fuel.
  • The conversion kit’s alcohol sensor determines the exact mix of alcohol in the fuel.
  • The conversion kit’s processor uses the fuel mix and shares information with the vehicle’s engine control unit to determine the exact amount of additional fuel needed:
    • Fuel mixture
    • Oxygen sensor
    • Engine speed
    • Acceleration & Deceleration
    • Temperature (accommodates very cold conditions)
  • Additional fuel is added through the kit’s injector in front of the throttle plate.
    • This is a standard technique used in racing
    • Fuel is atomized and ready to burn
  • The Processor monitors the fuel, the engine performance, and the exhaust to dynamically adjust the amount of fuel injected continuously.

Fuel Management System

The independent fuel management system provides sufficient control capability to enable these vehicles to pass stringent EPA testing.

Fuel Management System

  • Engine speed, throttle value positions and O2 sensor signals are borrowed from OEM equipment
  • Ethanol content and air temperature is provided from sensors we add to the vehicle
  • The processor is a race proven proprietary hi-speed controller processing information at speeds up to fifty times faster than the factory control module.
    • Algorithm based strategy with configurable Load & RPM axes to enable optimization in desired operating range
    • True Speed-Density algorithm allows for easier tuning
    • Integrated dashboard logic provides real-time critical system and engine functions
  • All electrical connections run through a common harness equipped with OE style metra-pack connectors. The harness is a universal application and can be adapted to fit most any application.

Supplemental Injection System


Read More On Performance

Payback Period

The conversion system has a short payback period under a range of scenarios

Breakeven Economics Analysis; 

Payback period in months for various of miles driven, fuel economy and State of Illinois rebate.  Shaded green payback in less than 2 years.

Miles Driven per year 15 MPG 19 MPG Avg. Fuel Savings per year
With Rebate Without Rebate With Rebate Without Rebate
15,000 14 months 70 18 90 $148
30,000 7 months 35 9 45 $296
45,000 5 months 24 6 30 $445

Key Assumption: Based on actual performance and 3 year average

  • Reduction in fuel efficiency with E85: 18%
  • Price spread of 72 cents between regular gasoline and E85
  • Installed price of the kit is $975
  • State of Illinois rebate is 80% of installed price
  • Fuel savings based on 50% city, 50% highway