I know 27.5 degrees of timing with a 2.0L with 2860 is pretty awesome. I think I saw Alex post a very long time ago that E50 seemed like the best mix, but I thought that was due to the fuel system limits. Without fuel system limits, Its hart to imagine why you'd choose to lower octane E30/E40/E50 over E85...
Im still not sure what the issue with full E85 is thought with this aux system.
Know what's better than E85? Methanol. No real good reason not to use M1 either really... Or.... E85 via the DFI injectors and meth for charge cooling through 4 different injectors.
We are so lucky to have these options, and I fear it will be many years before enough people grow a pair and start taking advantage of what crazy high octane can do for you... If you have enough injector and enough pump, why would you ever settle for less octane?
Back on the day, I had the "hook-up" on C16 fuel. I bought for $4 a gal. Everyone on the forums like, "how'd you make so much power?". I'd say "race gas". They would say, "I'm running 100oct too". I'd say, "no... REAL RACE GAS". The more you try to squeeze out, the more octane means, and straitified may have a great reason, but that this point, I don't have a clue what that might be...
I actually have a guess, but I'll see what STeve says...
Our fuel system maxes at 300whp on pump gas. To simplify it, lets use E100.
That takes our fuel system down to roughly 160whp on E100. So give or take 200-210whp on DFI and E70. Now... I think this aux system adds another 150whp of fuel using normal gas. But we are not talking about normal gas. Its actually only about 80whp of fuel on E85.
80whp + 200-210whp = not even 300whp of fuel on E85 (or so ). If you have a 350whp and try to run real E85, it could be an issue. But they do offer a bigger injector for the Aux system, so even on E85, it should be able to make some good power before running out.
Better solution? The setup he posted a link to on the focus ST forum. 4 injectors, tons of extra fuel. Or my old idea of AEM meth kit with 4 small meth injectors and a boomba intake spacer. That would let me run straight E85 and a healthy shot of meth, then everyone could keep on wondering and guessing how I make more power than their 100oct E30 tunes or 93oct tunes.