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Hello freebeard,
I've been keeping up with that thread as well. Intended application is an old 4x4 FJ-40 Toyota Land Cruiser. If axle-mounted motors get a sufficient torque/speed spread without having to change gears by the time my budget is available, I could go 1 motor per end or per wheel, but at this time it is far simpler to run everything through the transfercase and driveshafts to the existing front/rear live axle setup.
For off-road application, the setup to meet or exceed is ~6500 ft-lbs at the axle (with locking diffs, that can be all at one wheel, or divided amongst all 4, depending on how many are in the air/on a slippery surface) in low range. (250 ft-lb gas engine, 3.555:1 first gear, 1.96:1 low range, 3.73:1 axle gearing - total of ~26:1 gearing). Gearing lower (which is cheap down to about 66.5:1) becomes less important so long as sufficient torque is available. Gas engines need gearing to keep enough torque available at slow speeds without stalling the engine or burning up the clutch or torque converter. With insufficient gearing, you end up going too fast sometimes, which means more things busted/broken/bent. With an electric motor being a "constant torque" source below a certain RPM, stalling isn't an issue.
For on-road application, acceleration "feel" must meet or exceed the stock 125hp/250 ft-lb gas engine with 4-speed truck-type manual trans and average-ability driver. Pretty low bar to clear. If it isn't fun, it isn't worth it.
Self-contained range requirements are low - a stock used (cold-climate, so 9-10 bars showing on the battery still) 2011 Leaf exceeds my needs at present, even in winter. I'll figure out how to get it to remote off-road locations and how to recharge it there later. It'll be a fun commuter first.
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