Re: Dual motor design and transmissions

[Mason Convey <opossum@asu.edu>]

Kevin Lynn wrote:
+ Keep me updated on how your dual motor design is working for you
+ please. I'm building a really hot car using dual motors and am
+ trying to find the best way to utilize them.

Kevin (and all),
Our dual motor setup is working amazingly well. We expected great
things... and have yet to be disappointed. Our Gates Poly Chain GT
drive belts (Gates Rubber Company, Colorado) are the strongest things
I have ever seen. We ran the car at over 800 amps before the belts
were tensioned enough. The belts slipped numous times... and not a
thing happened to them. Once we properly tensioned the belts, the
motors ran well together. We have yet to finish our new telemetry
system, so it will be a few more months before we have some good data
on their performance.

+ Interestingly.. Paul Compton told me I should go with a automatic
+ transmission such as you're doing. Are you still letting the
+ automatic do the gear shifting? Have you thought about setting up an
+ electric shifter for the automatic?

We're about as happy as we can be with our Honda tranny. Our driver
supplies us with the transmissions, 3-speed Honda automatics. As he
put it, "I knew they would be perfect for your race car because I can
never get rid of them! No one ever breaks them, so I can't sell them!"
We put it through a lot of abuse... and it takes every bit of it. We
have sheared half-shafts in two, but the tranny has never gone sour.
We DO tend to "force-shift" the tranny, simply because the shift
points were designed around an ICE, not a motor. We can adjust the
upward shift points to approximately where we want them, but the
tranny doesn't seem to want to downshift soon enough for us. But then
again, we're talking about racing...

With our Honda contacts, we're looking at changing to a CVT soon. So
our research on automatics may come to an end within the next 6-12
months (optimistically speaking). But I'll post again when we have
more info on the setup we have right now.

	opossum





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mason s. convey

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