I put some 93 octane in it plus the very cold air and I'm having a blast! And with the snow on the roads it's like an ATV (4wheeler) that's legal to ride!
I have found that, 93oct, S/C, and cold air are a wonderful mix with the VX. The cool, denser air is Mother Nature's intercooler for the S/C in some regards, heh.
Wish my STi could benefit other than having an intercooler that get's Mother Nature's cold breath cooling it. Sure beats summer heatsink.
Gary Noonan
'01 S/C VX / '18 Forester XT