turning one rear wheel spindle into live one with electric drive

[max_frontal_area]

did a quick search but not much luck... wondering if i were to turn
my '80 front engined, front wheel drive diesel rabbit with dead rear wheels
(solid axle [torsion type] fixed spindles and 2 tapered roller bearings per wheel) into an electrically hybrid assist by driving ONE rear wheel.
the concept which is likely not new is to turn one of the rear wheels into a live, driven one by using an electric motor to be used during light/medium cruising.
i have been musing the possibility of removing the torsion axle and replacing it with IRS to be able to extend the exterior downwards and to upgrade the rear suspension simultaneously.
doing so would also allow options for adding a live axle from a small rear wheel drive car - providing mounting points match up.

these are quick questions i have in order to consider feasibility:

1 can it be clutched with an heavy duty A/C clutch
2 would a 20 horse motor be sufficient?
3 how much would it cost/ does one exist, to build a simple 3 position
controller?
4 can it be 12v DC so a generic alternator can charge the paired
trojan t-105*s

Completely gutted the vehicle could weigh 1700 lbs possibly even less,
which would keep the additional payload in a realistic realm.

at 65 MPG on diesel this could easily go over 100 MPG.

thank you for creative input and clarification!

[JasonG]

I want to do similar to the Jetta (once I buy one).

Toyota supras and Ford mustangs have IRS rear diffs and are about the right size as well as readily available in junk yards.
I plan to do one that way.

I plan on using a 240V 10HP AC motor and a VFD, but I'm comfortable with electronic controls.

[MetroMPG]

This thread has some discussion of rear wheel EV conversions:

http://ecomodder.com/forum/showthrea...tric-7372.html

[NeilBlanchard]

If you do this, I would suggest powering the wheel closest to the center of the road; so that it bounces less? It would be unsprung weight, probably.

On the other hand, if it is on the outside then it would push the car "uphill" because of the road crown -- this might be more stable in terms of resisting the yaw force?

[Ryland]

Being able to do this is going to require that you be able to adapt the rear end of a rear wheel drive vehicle to your vehicle and this is going to depend on your skills in this area, picking a vehicle that has a 4 wheel drive version is going to be the ideal way to go, VW has never built a 4 wheel drive version of the rabbit as far as I know other then the high end VW passat and as far as I know and the passat rear end might be the way to go but I doubt that it will easily bolt on so it will require a great deal of fabrication on your part.
Using a 12v system is not going to be the way to go, a speed controller for 12v that can handle 100's of amp is going to be very hard to find and most likely expensive, same with a motor powerful enough to drive a car, a 12v motor is going to draw alot of amps and require very heavy windings.

[max_frontal_area]

Originally Posted by NeilBlanchard

If you do this, I would suggest powering the wheel closest to the center of the road; so that it bounces less? It would be unsprung weight, probably.
On the other hand, if it is on the outside then it would push the car "uphill" because of the road crown -- this might be more stable in terms of resisting the yaw force?

been wondering that too. car will be "vacuumed" of anything not needed,
seats, panels, dashboard some glass replaced with plastic...
only thing inside will be steering wheel, driver seat, me-n-my wide one.
dont suspect a constant 10 horse push to produce much of a yaw
how much power does it take to push a small 2000lbs vehicle @ 60MPH
on a flat freeway?

at this point i am thinking to keep the splined shaft floating with 1" play or so
reason being the desire to use only 1 CV joint and to have the electric motor
soft mounted so it will auto align itself at all times, making provisions of course
for torque mounting.

if this idea is as easy to implement as i think it could be one could pull back a lot of older vehicles from the brink of extinction - and likely make them more efficient than some of the cleaner running vehicles you could by today.

[skyl4rk]

A hub motor might work for you...

Electric Car Hub Motors-Electric Car Hub Motors Manufacturers, Suppliers and Exporters on Alibaba.com

[max_frontal_area]

ryland, jasonG, i was thinking of using front end parts like the late pontiac did with the fiero. with that in mind you have a LOT of vehicles, sizes, projected loads, configurations geometries to choose from. no doubt having mc pherson
strutts protruding into the cargo area might make you laugh, but will quickly stop being humorous when ppl are being told stories of 3 digit economy - on a 30 yo car.

the other possibilty, which would be quick and dirty, would be to keep the solid rear axle and simply grind off the static spindle and graft a hollow one in its place. might be tricky though.

as for motor, how many watts would you need?. is a 10KW motor suitable -
run at 3/4 capacity? a big SUV is said to use 18HP at constant cruise.
how much can a lightweight compact possibly use?
if 12V is a no go, you would need a seperate specially wound generator
like Howard Hughes had in his jalopys to start his aircraft. he used aircraft
24V.

could it be done with 24V? is it realistic/doable to just have an on/off switch
and cycle on every time you want to accelerate, then off when u needa slow down???? is it possible at the same time to disconnect the motor electrically
so it would freewheel and not slow the vehicle terribly (regeneratively brake)?
of course you would use ryland, jasonG, i was thinking of using front end parts like the late pontiac did with the fiero. with that in mind you have a LOT of vehicles, sizes, projected loads, configurations geometries to choose from. no doubt having mc pherson
strutts protruding into the cargo area might make you laugh, but will quickly stop being humorous when ppl are being told stories of 3 digit economy - on a 30 yo car.

the other possibilty, which would be quick and dirty, would be to keep the solid rear axle and simply grind off the static spindle and graft a hollow one in its place. might be tricky though.

as for motor, how many watts would you need?. is a 10KW motor suitable -
run at 3/4 capacity? a big SUV is said to use 18HP at constant cruise.
how much can a lightweight compact possibly use?
if 12V is a no go, you would need a seperate specially wound generator
like Howard Hughes had in his jalopys to start his aircraft.

could it be done with 24V? is it realistic/doable to just have an on/off switch
and cycle on every time you want to accelerate, then off when u needa slow down???? is it possible at the same time to disconnect the motor electrically
so it would freewheel and not slow the vehicle terribly (regeneratively brake)?
of course you would use petrol engine to get it up to speed,
kill it and then engage electric drive...

i got the skills baby - if someone can size the motor and do the electronics.

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here is an update. in addition to the single CV joint and floating splined drive
shaft stuck through the hub, this splined shaft since it wont need to be torqued to one million foot pounds could have a quick release.
pop off hubcap, pull pin remove washer replace hubcap, once back in vehicle
pull lever which will slide motor along with shaft out of hub into securely latched "park" position. to eliminate parasitic drag from electric motor during
long periods of ICE engine to get it up to speed, kill it and then engage electric drive...

i got the skills baby - if someone can size the motor and do the electronics.

skyl4rk, what is the damage$ and how would you hang it?
please keep in mind i paid $300 for the whole car

--------------------------------------------------------------------------
here is an update. in addition to the single CV joint and floating splined drive
shaft stuck through the hub, this splined shaft since it wont need to be torqued to one million foot pounds could have a quick release.
pop off hubcap, pull pin remove washer replace hubcap, once back in vehicle
pull lever which will slide motor along with shaft out of hub into securely latched "park" position. to eliminate parasitic drag from electric motor during
long periods of ICE operation further increasing economy.

is this realistic? i think so

[Ryland]

My point with using the rear suspention from a 4 wheel drive VW is that more of it is more likely to line up and bolt on, but also keep in mind that the rear axle stubs of a VW rabbit bolt on, they are not welded on so you are not going to need to do any cutting of the axle stubs, but their bolt pattern is pretty small, maybe 3" with 4 bolts, it's been a while.
What I would do however is to buy a used rear swing arm, that way you can make your modifications to a rear swing arm that is not in a perfectly good car that if your project doesn't work out could be sold, otherwise you have a car that even tho you paid $300 for it is worth closer to $1,000 if it's in running condition.
to get a 10hp motor you are most likely going to need to go up to 72v or higher, look at the D&D motor web site, you might even write to them and ask about their custom wound motors and ask them what the lowest voltage for a 10hp motor is going to be but I suspect that no one will build one for you and that if you did get one built that you would need very large electrical cables going to it, 10hp at 12 volts is well over 600 amps... continues, go with 72v or 96 volts at they very least.
I would then be temped to graft on the rear end of something like the Honda WagoVan from the 1982-1985 as that had a solid rear axle for the rear wheel drive, then set it up like solectra did the Chevy S-10 conversions that they built and sold, with the motor sticking out the rear insted of sticking out the front, a very simple gear box or chain drive allows the motor to sit next to a very short drive shaft to allow for suspension travel without having the motor stick out the rear of the vehicle.

[max_frontal_area]

Ryland, yes i believe it is 4 bolts on the rear brake assembly.
i dont know how others are done which i why i thought welding would be required will check next trip to the wrecker...

the old rabbits were narrow cars, not tokyo streets narrow but old europe
narrow and with successive models they got wider perhpaps the rear from a recent all wheel drive might work... mistubishi also had ultra mini vans and toyota had a tercel 4x so there are options. i prefer the bolt on idea but will do some looking and bring a tape measure

ok, a 10 horse DC motor will need 72V at least. could a 20 HP motor be run on less voltage or is it simply not a good idea?
well i was hoping not to have to drag too many batteries around since it would be a hybrid and not full electric. to keep them to a minimum i would have to use 12v deep cycles, 6 ovem, looks like?
so what would you use for charging this bank of batts? regular alternator then DC to DC converter to feed the bank? or specially wound alternator.
and the controller for this system, would it be infinitely variable? and how much$$$

My idea with coupling the motor directly to the hub is so wonderfully simple
and electric motors are not sensitive to RPMs like ICE are, why do ppl always want to complicate life.
besides whips and chains are for the bedroom!