See if I got this right.
This engine's 9.7 : 1 compression ratio required a knock sensor to allow the use of regular gas. I learned that here.
The ECU will retard the spark (and possibly effect other changes?) so the engine doesn't detonate early....like all modern vehicles.

If you plan a "spirited run" through rolling hills on a hot day, would upping the octane let the ECU give you as much spark advance as it could?
Not talking speed-demon stuff, just brighter engine revs and better fuel economy.

 

Yes

 

+1 ^^^

Higher octane fuel will give you the rated horse power of 207HP and rated torque, 89 octane maybe, 91 for sure

 

Question: how does the ecu react with the knock sensor disconnected?
Reason I ask is this Ranger I just swapped a new motor into had the old knock sensor wiring chewed up by rats. Didn’t know until I pulled it apart. But other than the head gasket issue the truck ran fine prior to yanking the engine. Only in the last few weeks did the heads get really bad. I had worked on getting every thing operating as normal before the engine swap, and didn’t really have any SES lights until I kept the coolant topped off every day and got engine misfire codes.

 

It defaults to 87 octane spark timing, so less overall power running any octane