eFlexFuel E85 flex fuel conversion kits
Starting at $61.50 / month with 
SKU: U-EF-PLUS Availability: In stock - Free shipping
- Delivery time 2-5 days
- 5 year warranty with registration
Always Optimized Fully Automatic Flex Fuel
Cooler & Cleaner Engine
Complete System, No Tuning Needed
Up to 10% Increase in Performance 
Your Fuel System VerifiedDIY Virtual Load Sensor Tuning
Easily & safely create custom ethanol fuel maps based on your own vehicle's performance & modifications, without tapping into external load sensors - all from your laptop. Now you can augment your Ethanol fueling yourself, without touching your factory ECU and without jeopardizing engine safety.
Experience the VelvetTouch+
All eFlexFuel devices provide smoother and more seamless drivability than any other flex fuel system in existence. No small feat, our R&D team accomplished this with unrivaled attention to detail, countless long days & late nights, and a unique eye for optimization. The result of this "Velvet Touch" development? Our class-defining eFlexV10+, eFlexPro 2 & eFlexPlus.
Supercar Technology in your Daily Driver (or Weekend Warrior)
By installing the eFlexFuel kit, you're in good company. eFlexFuel conversion kits utilize technology found in the Koenigsegg Jesko, Dodge Challenger SRT Demon 170, and other top-tier performance vehicles. This tech is used to get the most out of E85, Gasoline, or whatever blend of the two you have in your tank.
Industry Leading, Free 5-Year Warranty (With product registration)
Nothing says, "We stand behind our product," like our free 5-Year warranty. We know what our kits are made of and we aren't afraid to put our money where our mouth is. You will not find a warranty like this anywhere else.
Expertly Engineered, Designed & Manufactured in Finland
Expertly Engineered, Designed & Manufactured in Finland. We have developed our hardware & software in-house in Pirkkala, Finland, since day one. Before shipping, we confirm every single control unit's functionality before shipping.
Technical Specs & Features
- Precise Ethanol Content real-time measured over 100 times per second
- Advanced signal processing filtering system in all input signals
- Shock-Proof & Weather Proof casing
- High Quality Wiring Harness with snap in connectors (no soldering required)
- Ethanol Tested & Approved fuel accessories (line, clamps, quick-connectors)
- Bluetooth 5.2
eFlexApp Main Features
Dynamic Gauge Screen
with Key Information
Choose Your Driving Mode
Dyno Proven Power Gain
Real-time Analog Data
for Sensor Inputs
Log History
with Real-Time Parameters
Please confirm device versions features at eFlexApp page
eFlexTuner Main Features
3D Fuel Maps
With eFlexFuel's Pro models, fuel maps can be observed in the 3D graphics window. The view can be rotated freely and selected fuel map cells are highlighted over the 3D map. The color-coded fuel map makes analysis simple.
Data Logging
All running parameters of the control unit can be captured and saved to a log file. Choose which parameters to display including date range. eFlexPro and eFlexMoto Pro log files can be analyzed in-depth with the eFlexTuner. Color-coding helps distinguish data points. (For example, the fuel mixture or the injector duty cycle.)
Log File Analysis
eFlexPro and eFlexMoto Pro log files can be analyzed in depth with the eFlexTuner. Data can be taken from an entire session or a specific timespan. The data is color-coded, which helps to distinguish e.g., the fuel mixture or the injector duty cycle.
Please confirm device versions features at eFlexTuner page
Testimonial
Dyno results
Chevrolet Corvette C5 2004 LS1 5.7
HP increase +18%
Torque increase +12%
Device: eFlexPro
Swipe for more results
Peak power gains do not always tell the whole story! It's important to look at power gains across the entire RPM range / dyno curve, A.K.A. power "under the curve." Power gains under the curve will have a greater impact on driving experience. This is because gains under the curve impact the broader usable powerband, whereas peak power is momentary - only at one point in the RPM range.
If peak gains are 5% while max gains under the curve show 20%, this +20% increase is a better reflection of how your driving experience will change (you'll certainly feel that increase!). You want to feel the difference in the seat of your pants, and this is where power under the curve plays usually the biggest role.
+ Compare products
 |  | |
|---|---|---|
| Features | ||
| VelvetTouch+ | ||
| Free 5-Year Warranty (with registration) | ||
| Ethanol Content real-time measured over 100 times per second | ||
| Advanced signal processing filtering system in all input signals | ||
| Shock-Proof & Weather Proof casing | ||
| High Quality Wiring Harness with snap in connectors (no soldering required) | ||
| Ethanol Tested & Approved fuel accessories (line, clamps, quick-connectors) | ||
| Bluetooth 5.2 | ||
| Analog Wires for External Sensors | ||
| eFlexApp | ||
| Ethanol content | ||
| Vehicle speed | ||
| Engine RPM | ||
| Duty cycle | ||
| Fuel temperature | ||
| Ambient engine temperature | ||
| Injector activity | ||
| Cold enrichment | ||
| Device status | ||
| Driving mode selection * | ||
| Cold enrichment custom setting (created with eFlexTuner) * | ||
| Save RPM based enrichment with driving mode selection (created with eFlexTuner) * | 1 | 3 |
| eFlexPro view for analog data | ||
| eFlexTuner | ||
| RPM. based 2D fuel map * | ||
| Fault codes | ||
| Data logging | ||
| Fuel map adjustment | ||
| Log file analysis | ||
| 3D fuel maps | ||
| Sensor linkage | ||
| Cold start adjustment | ||
| Virtual Load Sensor Tuning |
* Does not include in eFlexV10+ devices.
+ What's included
- Control unit (3” x 5 1/5” x 1” in) x 2
- Ethanol sensor
- Wiring harness specific to your vehicle with an external temperature sensor x 2
- Two additional analog inputs that plug in to the engine’s own sensors (MAP, MAF, TPS or WBO) - included only in eFlexPro
- Cable ties
- Male fuel injector connectors x 2
- Fuel hose
- Fuel line quick connectors
- Fuel line disconnect tool
- Hose clamps
- Installation and User Guide
+ Installation
- Installation info
- General Installation and User Guide is included in the product package.
+ Returns
We always verify compatibility of the purchased product with the customer’s vehicle, so you don’t need to return or exchange your kit. If you must return or exchange your purchase, please contact us within 30 days of receiving your order. Your intent to return must be in writing, include a reason for return and sent to suppor[email protected]. Please include your reason for return/exchange.
The team at eFlexFuel will then issue a return authorization number (RMA) and shipping instructions. Please be advised – we are charging a $100 restocking fee. and be sure to buy insurance for the return shipment because we’re not responsible for returns that get lost or damaged in transit.
More About Returns+ Warranty
eFlexFuel guarantees its products are free of manufacturing defect for 2 years of use.
If you wish to extend the limited liability warranty to 5 years, please register your product here.
More About WarrantyWhat's included in the eFlexPro E85 flex fuel conversion kit / Installation
Note: If your vehicle 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.
Not legal for sale or use on pollution-controlled vehicles