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2001-2005 Impreza WRX STi E85 Flex Fuel Conversion Kits

Increase the Horsepower of Your Turbocharged 2.0L 4-Cylinder by up to 20%

The 2001-2005 Impreza WRX STi was the first STi introduced directly to the North American auto market. Though its engine was a little smaller than the next generations of STi sports cars would be, this generation had the best racing suspension of all. It was very stiff and rigid which didn’t always make for a smooth ride but when it comes to cornering, the stiffer the better. No roll. No sway. No slop in the turns. Now imagine increasing that horsepower by up to 20% in an afternoon – by adding one of our plug-and-play E85 flex-fuel conversion kits engineered for your Impreza WRX STi.

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

Introduction

The eFlexPlus and the eFlexPro are so easy to install that you can do it yourself in an afternoon and have your car running any mixture of E85 flex-fuel and standard gasoline the same day. Both come with a handy phone app that allows you to monitor the fuel mixture and switch between efficiency and performance profiles effortlessly. The eFlexPro comes with the additional eFlexTuner software that allows you to tune your turbocharged engine on any mixture of fuel above E50. Order one of these for your 2001-2005 Impreza WRX STi today and increase your horsepower from 261 even up to 335.

Installation

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 & ModelSubaru Impreza
Years2001-2005
Engine2.0l / EJ20K / EJ207
Power261 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.

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