I think the fuel here is very borderline (especially the winter mix) and I have been investigating different ways to bump the octane a point or two. Don't usually notice any problems but sometimes it can be a little "surgy" like the ECU is working too hard to keep everything happy. I had heard that up to a couple gallons of E85 would be OK and give a boost to the octane. I would be perfectly happy with 93 gas if anyone had it around here anymore.