Thanks Hussain,
This is really a BIG help !
If you ran from south east to north west on the long runway,
the total length of the PAVED track was 9,200 feet.
If I understand your words,
that means Phillip ran 5,280 feet
(1 mile) and reached 197 mph.
He then kept the throttle open an ADDITIONAL 3920 feet
( about another 3/4 mile) before he entered
the grassy area at the end of the track.
That would account for the increase
from 197mph to 220 mph.
The grassy area is about 1,700 feet long.
Does this sound correct ?