A system designed to allow a Subaru Tecnica International (STI) vehicle to run on varying blends of gasoline and ethanol, up to 85% ethanol (E85), is an aftermarket modification package. This conversion necessitates components like a fuel sensor to determine the ethanol content, recalibrated engine control unit (ECU) mapping, and potentially upgraded fuel delivery system components, depending on the power goals.
The significance of such a modification lies in its potential to enhance performance due to the higher octane rating of ethanol, while also providing the option to utilize a more environmentally friendly fuel source. Historically, these systems have been implemented by enthusiasts seeking to maximize their vehicle’s power output and reduce dependence on traditional gasoline, leading to the development of specialized products tailored for specific vehicle makes and models.