There are various things going on with "ACN" gas, but an ethanol blend is NOT one of the issues. If your car seems to be running OK, stick to a non-ACN map.
86 FZ 750
98 Legacy GT Wagon, silver (original owner, 152K miles)
**COBB - full exhaust (includes EL coated header), SS, F & R STB's, rear bar, stage-2 DOHC heads (P&P w/street cams) & stickers.
--Non-COBB - 99 RS 16x7 rims, 225/50-16 P Zero Nero M&S, ACT clutch, Exedy LW flywheel, Grimmspeed intake spacers, SS brake lines, modded WRX rear bar mounts & a Crawford modded STi NA SB, in & running!
99 Impreza L Wagon, silver
**COBB - F & R STB's (wife's car, original owner, 110K miles).