I am interested in buying an 04 viii gsr that is currently running on a tune with E85. One problem is that the nearest e85 pump is about ten miles away from me, so I figured if I had an option to switch between e85 and 91 octane maps, would it be possible? What exactly would be needed to set it up so with the flip of a switch and different gas in the tank (filled from near empty)it would work? Thanks

-Lucas

 

You will need:

1. Tephra patched ROM in your ECU
Read:
http://evoecu.logic.net/wiki/TephraMod
https://www.evolutionm.net/forums/ec...hramod-v5.html
https://www.evolutionm.net/forums/ec...6-testing.html

2. Way of switching between the 2 maps, either using the Intercooler Sprayer (ICS) switch, or an Alt-Map harness
Read:
http://www.dsm-ezine.com/evoVIII_adc_switch.html
http://www.dsm-ezine.com/orderpage1.html

3. ECU maps (fuel, timing, boost, etc.) for both fuel types.