I'm running HPTuners. I believe I had those parameters available even for my 2014 SHO.
To answer the OP's question, I ran 87 in the Fusion Sport for quite a long time. The OAR was +1.00 and inferred octane was something like 86 or lower (I remember it being lower than 87). Not very good for performance.
* 2017 Fusion Sport, 12.7 @ 108 mph tune-only (early tune of mine, bad trans settings), full trunk w/ lunch, and dirty paper air filter
* 2014 SHO non-PP, 12.4 @ 111 mph tune-only, all day long with dirty paper air filter and worn out 30k RS-As