I hadn't thought about that - I was thinking the old Oldsmobile Rocket Fuel setup meth injection / hobbes switch, but e85 under boost is a helluva thought. I had thought about that for DW ( high compression and running e85 all the time) but realized since I don't have a clue on the route, I won't know where any stations are.
slight derail, but I'll toss it out here anyway. Assuming the built-in ECM worked adequately with the engine NA, can you drive just the secondary set of injectors with a Mega Squirt using the same sensors or would it make the signal from them get screwed up? I figure you could use the MS for the whole thing, except the application I'm thinking about controls the trans (e40d)