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2020-2021 Challenger RT 5.7L HEMI E85 Conversion Kit

Install This Flex Fuel Kit Yourself and Increase Your Horsepower By Up To 12%

The 2020-2021 Challenger RT 5.7L is a slightly smaller HEMI than its SRT siblings but it still has the power to spare while sparing you a few bucks at the pump, as well. Though it’s not quite the HP monster that the SRT8 is the Charger RT’s top speeds and torque remain quite impressive. With our E85 conversion kits, your 2020-2021 Challenger RT can reach its potential with an up to 12% increase in its overall horsepower.

No tuning required!

$699 List price $874

Starting at $61.50 / month with Affirm logo

Truspilot consumer rating 4.7 SKU: U-EF-PLUS
  • Free shipping
  • Delivery time 2-5 days
  • 5 year warranty with registration


DIY install one of our E85 conversion kits, eFlexPlus or eFlexPro, and start running any mixture of E85 that you see fit. They are plug n’ play, easy to install, and you can experience an increase in HP of up to 12% almost immediately. Your 2020-2021 Dodge Challenger SRT8 will see differences on the track and at the pump. With the eFlexPro, you can start tuning your Challenger RT 5.7L HEMI with a mixture of E50 or higher.


DIY level

Plug&Play installation with some modifications - An experienced mechanic will install in 2-3h. For first time DIY installation, expect to double the time needed.

Technical specs

Make & ModelDodge Challenger
Engine5.7l / T / EZH / Hemi V8 MDS
Power370 hp
Fully Automatic Flex FuelAlways Optimized Fully Automatic Flex Fuel
Cooler & Cleaner EngineCooler & Cleaner Engine
No Tuning NeededComplete System, No Tuning Needed
Increase PerformanceUp to 20% Increase in Performance
Flex Fuel System VerifiedYour Fuel System Verified
Dynamically adjust engine tune to match fuel
Available performance and eco tunes
Select performance or eco tunes via eFlexApp
Create and save custom dyno tunes
Pro grade eFlexTuner tuning software

+ What's included

+ eFlexApp

+ eFlexTuner

+ Installation

+ Returns

+ Warranty

What's included in the eFlexPro E85 flex fuel conversion kit / Installation

Note: If your car is modified you can use E85 with eFlexFuel. If this is the case, please list all the main engine modifications on the checkout page. Our technical team will ensure that your setup is fit for E85.

* Power and torque increase depends on your engine technology and/or your custom built of the engine.

Prop 65 Warning
Warning signNot legal for sale or use on pollution-controlled vehicles

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