Never did make anything out of it because I never came up with a practical application. Even though I really enjoy working with outrunners (you know how much I've done with them), I prefer using inrunners due to their greater performance in a smaller package.
However, my XLB is still looking for a suitable motor and it has a center diff... Thinking something like a 4025-4035 might be suitable. The diameter is my only concern, because the motor mount was designed for a 45mm maximum diameter motor with 30mm bolt spacing and M4 screws.
EDIT:
Patrick, a suggestion for you: send one of your 40mm diameter outrunners my way for testing purposes in a car. Something with a stator length of 25mm-35mm and a kv of just under 500 and a shaft diameter of 5-6mm. Then we can see what those motors are really capable of
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