I have some tables and info from Flying to the Limit, by Peter Caygill. Its a book compiling RAF flight tests of various single engined WW II fighters.
For the Mohawk IV with the wright cyclone it gives the following
Height 10 000 , 14 000 , 20 000 , 26 000 , 28 000 ft
TAS mph 290 , 302 , 292 , 277 , 271
Height 10 000 , 15 000 , 20 000 , 26 000, 30 000 , 32 000 ft
time from start min 3.9 , 6.2 , 8.8 , 13.3, 18.0 , 23.2
Max speed was 302 mph at 14.000 ft and max climb was 2600 ft/min at 8000 ft. Climb rate did not drop below
1000 ft/min until 27,000 ft.
The Mohawk III with the Twin wasp does not climb as well.
top speed 300 mph at 10.000 ft
max climb rate 2,260 ft/min at 9,600 ft
time to heights 7.3 min to 15 000 17.5 min to 26 000 ft
Hope this helps
Slaterat