Mark is right and 280 is a bit rough still.
The thing with going to fast is that it creates to much heat so that is why you do it at a lower speed and move it throw the entire bore. Remember all you are doing is honing which improves the shape, geometric form and surface texture that is already cut.
2014 V6 Deep Impact Blue Mustang, Borla Type S, 2.73 (Uughh need 3.73)
1989 Sonic Blue Mustang LX Coupe, 349 ci,
392 rwhp 424 rwtq....Mustang Dyno
"There are three kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." -Will Rogers-