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Old 01-21-2009, 11:47 PM   #13 (permalink)
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LOL I forgot about the no diff thing... would be great in a straight line though!

Ok, so diff stays, motor gets mounted to diff... IRS is still a better option though, b/c with the motor mounted hard to the diff, it's putting more weight on the suspension. with IRS, you're putting no more weight on the suspension than was already there, and you're not incurring any more frictional losses than you would be with a solid rear axle.

In fact, I tend to think you're actually incurring slightly less losses with IRS, b/c you're only subjecting the diff itself to fluid drag, and the axles never see the associated "swimming".

Of course, given that CV axles are most efficient when working in a straight line (in a line that would be suited to a solid axle), you're probably losing that same efficiency gain b/c they're almost never straight.

It still would reduce suspension strain though, (unsprung weight) which is everyone's complaint when coupling motors directly to wheels, even though you can get rid of a large amount of weight at each wheel when using electric motors. (You don't need brakes anymore, technically.) (Legally, you still need them.)
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