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Discussion Starter #1
What do we really need out of our EV automatic? We want it to drive like a normal car while getting GREAT mileage.....LOL

There are many commonalities with an ICE transmission as it is doing the same job and it can not tell what is turning it. The huge benefit to electricity is that at stop lights, it can sit and not use any energy. It does not need to "idle".

We can use a torque converter or not, but the automatic transmission does have one problem. On early automatic transmissions, it needs to be signaled when to shift up and down, but there is no vacuum signal to modulate the transmission shift sequence.

On the later units, they were cable actuated by using the engine throttle linkage
to set the relationship. There was a bell crank arrangement that tied the throttle position to the transmission shift pressure signal.

And finally, on the late electronic transmissions, it uses a combination cable and TCU module to over see the shift process.

All three can be "band-aided" in some fashion.

The early vacuum units can be made fully manual shift. The cable units can have a custom proportionating bell crank fabricated. The electronic transmissions can use an aftermarket shift programmer like the "Opti-shift" to regulate the shift.

Message: DO your planning way before you do the build.

Miz
 

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All that's really needed in an AC drive is a semi automatic three speed transmission.

It has all the advantages of a fully automatic transmission, but is relatively simple. It requires no clutch no torque converter, and no dedicated reverse gear. The driver can control up-shifts manually, whilst down-shifts can be handled automatically.

Does anyone think there's a market for such a thing ?

Answers please !
 

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Discussion Starter #3
Yes, a semi-automatic transmission would be fine in an AC or DC system.

But some people like it to drive like a normal car for other family members....So, an automatic shift option is needed.

After driving a full manual valve body on a street car for a while, I found out they are much too rough shifting (up and down) to be in a normal type family car.

If one were to install a street/strip kit that retained automatic shifting and would shift manually too, that would be perfect!

The torque converter needs to go in any event. The electric motor stops when the car does and you need the positive drive coupling that the converter lacks.

The market depends on how many people use automatics. I do not know. Certainly more will try it if it exists in a ready built form...Or maybe a kit to convert theirs.

Miz
 

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When you talk of "driving a manual valve body", was that an auto transmission converted
to manual?

The system I have in mind could conceivably be switchable between either semi auto or fully auto, although controlling a fully automatic shift might take some development.

I imagine that the gearbox would come as a ready-to-fit unit, together with a kit of electrical parts (wiring, controller etc.), and an instruction manual.
 

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Discussion Starter #5
The system I have in mind could conceivably be switchable between either semi auto or fully auto, although controlling a fully automatic shift might take some development.
Actually, that exact transmission was built by Ivan in his Sonoma truck.

It is an 4L60 with the torque converter removed. It has an "Opti-shift" controller that provides full automatic AND manual shifting. It also has a tachometer drive signal ant several other features. It is infinitely adjustable and can suit any motor/load combination.

http://ivanbennett.com/ev-trans.html

Miz
 

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Discussion Starter #6
When you talk of "driving a manual valve body", was that an auto transmission converted to manual?
Yes, it was a powerglide. Converted to full manual and direct drive.

It is here:
http://www.diyelectriccar.com/forums/blog.php?bt=1866
(about the idea)

http://www.diyelectriccar.com/forums/showthread.php/building-ev-powerglide-transmission-77105.html
(About the actual transmission build)
http://www.diyelectriccar.com/forums/showthread.php/1930-model-roadster-build-59659.html
(About installation in the vehicle)

A lot of reading, but a lot of information too.

Miz
 

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yes a power glide would work... but the 4L60E/4L65E is much more readily available and offers a much broader operating range. Of course the real answer is a unit specifically designed to take full advantage of the benefits of using magnetic fields to drive the input elements. It just so happens that in 1986 such an Idea occurred to me. and I am now developing it. I know.. what took so long? Waiting for battery technology to catch up I guess. To reveal anything more at this point would require a non-disclosure agreement.
 

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looking to get involved with like minded forward thinking people, preferably in southeast Arizona, but any interest is welcome. got the green light to attend EVCCON 2013. my 16 yr. old step daughter wants to join me, hope it happens.
 
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