I've searched with no clear answer. I'm Thinking about running a 91 pump gas tune and E85 tune with a pulley swap. Has anyone done this? Essentially I would have 2 tunes and 2 different pulley sizes. Thinking 2.85 griptec for 91 and 2.72 or 2.75 for E85. I plan to track it occasionally and would like the higher power for those days. Let me know your thoughts.