Doing some research for a brochure layout project for school regarding "Promoting green" started reading about E85 conversions and ethanol blended gas...in my research i got a little curious about the conversions and was looking on here for some info. Anyway, i was wondering what the difference is in a E85 "tune" which i read about on here, and the E85/Flex Fuel conversion kits that i see for sale? I even see some for sale specifically for Subaru Boxer engines, any information would be helpful. Sites with conversion kits: http://www.change2e85.com/servlet/Detail?no=105 http://www.mye85kit.com/index-Subaru_2000-2009_E85_Conversion_Kit.html
There is a thread about this on nasioc, some guy did a bunch of his own research/experiments on his own car, and its pretty in depth. http://forums.nasioc.com/forums/showthread.php?t=803341 I haven't read all of it, but its pretty interesting nonetheless.
Main difference between the "conversion kits" and a tune for it is that the kits do not optimize the engine management for E85, they just squirt in the extra fuel needed by overdriving the fuel injectors some. On a stock car, you could get away with that, if you have any mods, it is just not going to work out. Most of the kits I have seen just plug in to the fuel injectors and the harness and interpret the signal being sent by the ECU and modify it to add the extra amount of fuel needed to run E85. They do nothing with any other parameter. Will it allow you to run E85 on a stock car...yeah probably. Will it be optimized? No. Will you run out of injector on a stage 2 car with stock injectors trying to use one of these? Most definitely.