The front motor would be optimized for higher speed and used in a greater proportion to the rear at high speeds, leaving the power distribution more rearward at low speed (when acceleration is greater so load transfer to the rear is significant). Logically, in this scenario the two motors in the rear are identical to each other and simply each driving a wheel.
I think this would be something like two identical rear ratios at let's say 14 and a front at 7 - for a 2:1 ratio. The problem is that this will not take you up to 250 mph. The rear motors cannot deliver the power at those speeds, and the front is underpowered and too high RPM for 250 mph is required - the spread of the ratios is not wide enough. But I like the idea that at high speeds, power is mostly delivered by the front, and I think that will make for better high speed driving. So the ratios I propose are 18 for RM1 (rear motor 1), 10 for RM2, 6 for FM, for a 3:1 ratio of the reduction gears.
0 - 60 mph, 100% power on all three motors, torque ratio (RM1, RM2, FM): 60%, 35%, 5%
60 - 150 mph, power is cut to RM1, 100% to RM2 and FM. Torque ratio: 25%, 55%, 20%
150 - 250 mph, power is cut to RM1, RM2, and 100% to FM. Torque ratio: 0%, 30%, 70%
Electrowrks, what is the effect of switching from delta to wye in the stator configuration of a PM motor?