[ShadowReaper]

Recently came from Florida were 93 octane is practically everywhere, aaaaaaand now I'm in Colorado where I believe there isn't a single 93 pump. The premium gas here is 91 octane.

The power loss is extremely noticeable, and I can't take it anymore. Maybe elevation has a factor in to with the feeling.

I've been referred to add a little e15 to the tank. However this to me sounds sketchy. I have also been referred to add a little 100 octane to the tank.

I just want to at least match 93 octane again, nothing less. Whats the best way to go about this?
How would this work with tuning, considering every mix will be different.