is higher octane really any better for the 4 cylinder?

I dropped 2 or 3 gallons of 89 into the truck's tank, when acquiring chainsaw fuel. The computer definitely noticed something was up, and for the next several miles, instantaneous mileage shot upwards and a very light throttle provided "lots" of acceleration.
Didn't really pursue this avenue further. Just noticed that the truck noticed.

 

it definitely has a tiny bit more power with 91. Since owning my 21 I’ve traveled back and forth from NC to NY to visit family about 4-5x it’s about 1400 miles round trip. I 100% notice less shifting around on the highway and about 1-1.5 better mpg. I only use 91 on long trips still waiting on that “tune” to be released which seems to never be coming to help. I still get gear hunting on 91 but I have a mid rise topper and some 265/75 AT’s which don’t help but I do have an LCE header as well.

 

4banger for my 97 said atleast 87. If i use 91 I would just rather sc it.