[Beviking]

All of the motors in all of the Mustang's since 2011 make more power on premium than regular. They have adaptive ecus with tables that allow the car to add timing until knock is detected. The owners manual will say on the 5.0 specifically the hp rating is based on premium and you will make less power on regular even though it's fine to use.

Yup, there’s fine print with the hp statement that the hp rating was taken with premium fuel. Partly why I did my own “testing”.

 

[mriteck]

Damn fine print gets ya every time! LOL

 

[65 k car]

93 = not "harder to ignite", but slower burning rate.