Author Topic: Powerglide transmission use in an EV  (Read 12568 times)

Offline mizlplix

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Powerglide transmission use in an EV
« on: December 11, 2012, 01:31:00 AM »
The Powerglide transmission is a really great one for EV use.

It's light weight, single planetary, low internal friction design
has made it a favorite of drag and oval track racers in the USA.

Why not adopt it into our EV family too?


This is a TCI built, direct coupled, full manual unit with an HPEV AC50.


There is a really good discussion thread here:
http://www.diyelectriccar.com/forums/showthread.php/reasons-why-automatic-gearboxes-work-evs-29101.html


And a good conversion /rebuild thread here:
http://www.diyelectriccar.com/forums/showthread.php/building-ev-powerglide-transmission-77105.html

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline mizlplix

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Re: Powerglide transmission use in an EV
« Reply #1 on: December 15, 2012, 06:06:34 AM »
Powerglide transmissions can be changed easily and adapted to suit almost anything.

As in this shortened, direct drive version.

The tailshaft can be removed and an adapter plate installed to cut off 11" from the rear portion if needed also.

Thanks to matthieu149 on this thread for the CAD image:
http://www.diyelectriccar.com/forums/showthread.php/planning-mazda-rx-7-conversion-72028p5.html?highlight=powerglide
His thread is an informative read for anyone needing a short transmission solution.

Powerglides come in several ratios.  Basically there is a 4/6cylinder ratio @ 1.82:1 and a V-8 ratio @ 1.78:1.

The 1.78:1 versions are slightly more robust in the planetary carrier then the others, but either is fine for our EV usage. 

The powerglide is popular because they onlt have one planetary, which means lower internal friction.

You can actually get every part in the aftermarket to build a complete transmission!

Hughes Transmissions of Phoenix, can make a 550 RPM stall converter to make it suited for EV usage.

 
Some have retained the torque converter, placed an aluminum plate at the front of the motor to mount a power steering pump, alternator, vacuum pump and Air-condition compressor to be driven off the auxiliary motor shaft.  They set their controller to "Idle" the drive motor at 50 RPM's when stopped.  A really nice/cheap way to get all of the expected comforts.
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline mizlplix

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Re: Powerglide transmission use in an EV
« Reply #2 on: December 15, 2012, 04:42:31 PM »
All EVs over 2,000lbs need a transmission with at least two gears.  Rarely does anyone need three.  So,  You wind up turning those extra gears and pulling that friction needlessly. 

The perfect EV transmission has not been invented yet, but until it comes along, the Powerglide will do.  It is cheap to buy, easy maintain and operate.

It has a great gear ratio spread for an electric motor.  It is light weight and reasonably compact too.

It is the only easy to find, mass produced automatic transmission with only one planetary gear set for minimum frictional losses. 

The closest other two speed automatic, is Fords "Ford-o-matic", but it was only produced a couple of years and is hard to find. 

For those wanting the ultimate in two speeds might want to check out the one made by Coleman.
It offers any ratio you want in low and when shifted to high, it disengages the lower gear cluster. 
The input is coupled to the output shaft directly.  It has almost no frictional losses at all when in high gear.

With a 2.2 low gear and weighs 37 lbs total...Cost is $1,600USD. 
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline mizlplix

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Re: Powerglide transmission use in an EV
« Reply #3 on: April 13, 2013, 10:06:44 PM »
___________________________________________________________________________ __________________________________________________________________________
   Some interesting powerglide mods

I never stop searching for new ways to modify and adapt
automatic transmissions to our EV's. I have discovered
some recently that might be of use.


This is an update and not been tested by me:

I have been pondering the question of how to take a "Craigslist" transmission
and convert it to EV use without a lot of money. It was a challenge but I believe
 I have the answer. Several of these mods have been done by me at different
 times and on different transmissions, and one in particular is a new one for me.
While I believe this will work, I take no responsibility if you want to try it.

1. If you find a decent powerglide, or any other automatic transmission these
mods should work on all except the later electronic ones. (these instructions are for a powerglide)

2. Locate the pressure port for low gear band apply and install a hydraulic flow
control valve there. like this:


Drill and tap a hole in the transmission case or pan (at least 1/4" NPT), run a
hose from the valve to the new oil return port. Open the valve fully as a starting
position. Drive the car and close the valve a bit at a time until the car takes off
like you want it to.(softly as throttle is applied). Like an automatic clutch.....

3. Clean out the pan and install a new filter while you are there.

4. Buy a direct drive coupler and the correct flange from Speedway Motors. Their
drive has a removable and adjustable flange while other kits do not. They have
flanges for early and late Chevy engines. You need to get the special snap ring
with it too. (About $150-$175)

5. Do not put a hose to the modulator, leave it alone and the transmission will run
in high pressure mode.

6. The last mod is a little trickier. The modulator presses or pulls a rod in and out
to regulate the shift point RPM. if left alone, your transmission will only shift up at
very high RPM's. (I can only guess at 4,500 or so)

Each car built, each driver, every terrain and traffic condition-has their own
best shift point. You can alter this point by unscrewing the modulator and pulling
out the little push rod that sets the pressure and shortening it a little.

It would take several tries to get it close to what you need and you would need
 to drain and refill the pan each time......

OR remove the modulator completely and make a replacement fitting with a screw
 adjustor so you can do this easily and quickly.

And like the hydraulic valve setting, once set, you will probably not need to move
it again, but you would have that option.


All of these mods should give you a 2 speed transmission that needs no external
pump. You should have either an automatic or manual shift. And it would be
adjustable for an easy or abrupt take off, an adjustable RPM for the shift point
and doable for under $500 if you watch and are careful. All without having to
disassemble the transmission if it was decent to start with.

The only down side: You have turned the low gear brake band into a clutch and it
will wear faster than normal, but the lighter weight the vehicle, the longer it will last.
If it ever gives trouble, you will always have high gear and will not be stranded. I
would recommend you install a Kevlar racing band in the beginning if you can,
 they are tough as hell....

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline few2many

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Offline mizlplix

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Re: Powerglide transmission use in an EV
« Reply #5 on: April 14, 2013, 03:38:24 PM »
That is just an old Saginaw 4 speed gutted.  Honestly it is a $400 core that has been gutted and some aluminum spacers installed.
You are still turning ALL the mainshaft and counter shaft gears all the time.  The rotating assy alone is 20Lbs.

The other transmission is 37 Lbs in total.  When It is in high, it is locked up straight through and the countershaft is not turning.

Big difference in friction for 50% more cash,

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.