What motor are you using? Determine the final drive ratio first, it is different for different number of turns in motor.
For example, for me, the final drive ratio is about 6.5 recommended by novak for my ss.
Since your internal drive ratio is 2.435, then you can use this formula.
2.435 x 98 / no. of teeth on pinion = 6.5
No. of teeth on pinion = 2.435 x 98 / 6.5
= 36 teeth