This is SOTP only, no instrumentation... The closest station that sells 93 octane is 35 miles away, but it's on the way to the kids house so I've been able to run 93 for the last month or so. Yesterday I had to fill up with 91. There's a noticeable difference in passing performance with the 93 vs 91 (the torque limiting suggests no difference off the line). On 93 I have to be careful to get fully out of the lane behind a car passing so the autonomous braking light doesn't come on, and it's the fastest 60-100 car I've owned. On 91 it's just "OK". I wish there was a way to get 93 easier...