Dave,
Thanks for the answer.
What I do is convert the times to a speed comparison chart.
57.0 = 96
In the above examples if I round down to 57.3 is 93 and 57.4 is 92.
I handicap by hand and have my track comparison charts along my back wall. so handicapping is as easy as comparing Belmont's sprint rating of 93 to Oaklawn's 91 to Turf Paradise's 97.
So I'll round to the nearest fifth which should be more accurate.
Until I run into the 10k time of 57.5
Then I'll round up or down depending on the other sprints for that track.