Home made hybrid (using access to 5th gear on FWD transaxle) - Page 2 - Fuel Economy, Hypermiling, EcoModding News and Forum

diesel_john · 04-02-2008, 10:41 AM

i have driven a dyno off the back of a FWD front wheel drive trans. The PTO power take off came out through the cover with a seal as described, But i coupled a drive shaft straight to it, so no side load. It was a Dodge Daytona trans. with a prototype 3-valve V8 so nothing else was the same.

Back to your idea, you might want toextend the shaft a inch further and put a bearing on the end. But if it already has two bearings on the shaft then you are OK.
What RPM's are possible with the motor? Does an electric motor need all that reduction? I would think motor's would make torque a zero Rpm so no need for gears.
I always try to think, how to couple direct to a wheel. Or Placing a two shafted motor in the drive shaft. No belt loss. Just a little bit of regen would add up, wouldn't it? Just brainstorming. Could you shorten the drive an inch and put a cog pulley in between the trans and constant velocity CV joint?

bennelson · 04-03-2008, 10:52 AM

Sounds like a great project! Keep us continually posted!

I have two nice motors that have that same hydraulic pump connection.
Let me know if you come up with a good way of connecting that to some sort of pulley or driveshaft.

There are lots of motors like that out there cheap and used that would be great for experimenting if that connection wasn't so useless!!!!

What car and/or engine are you planning on doing this to?

tasdrouille · 09-17-2008, 03:44 PM

So, anyone have an idea how to make those hydraulic pump motors usable? I can get a 2kw 24vdc pump motor for cheap and would like to somehow belt it to the crank pulley.

Ryland · 09-17-2008, 04:41 PM

Quote:

Originally Posted by tasdrouille

So, anyone have an idea how to make those hydraulic pump motors usable? I can get a 2kw 24vdc pump motor for cheap and would like to somehow belt it to the crank pulley.

last i checked those pump motors were 10% duty cycle, or about 6 minutes of use out of every hour, any more then that and the motor will over heat melting the insulation and starting on fire.

tasdrouille · 09-17-2008, 04:54 PM

Quote:

Originally Posted by Ryland

last i checked those pump motors were 10% duty cycle, or about 6 minutes of use out of every hour, any more then that and the motor will over heat melting the insulation and starting on fire.

That's what I get for not knowing jack about electric motors. Glad I asked.

metromizer · 09-17-2008, 05:41 PM

I haven't had a metro trans apart, but with enough ingenuity and motivation it is possible to extend transmission shafts... it's just not easy. It there were a way to drive another gear off of 5th, employing yet another shaft, you might be better off. Again, I've never had one apart. I have extending a couple of precision shafts for a hybrid car back in 1982 or so, so I do have some real world first hand experience with that.

I don't twant to sound like a wet blanket, just look at ways to overcome some of the potential issues I see coming your way.

In most cases, those transmission shafts are hardened, very straight, and have presicion ground surfaces on them. What this means to the modifier is drilling, boreing and cutting a keyway might be out of the question unless you aneal it first, then reheat treat it later <hold that thought>. Another way I have heard of, some company that adds a 5th gear to a 4 speed box, is to machine the shaft, make an extension, then vacuum furnace braze the two together. Then re-heattreat it. I understand it was quite a development project for the 12 person company that did it.

Then problem with reheat treating any previously harded shaft is several fold. You need to tell the heat treater exactly what the material is so he can apply the correct recipe for that specific steel to either anneal, or more importantly re-heatreat it. If you work with a heat treat house beforehand, they can hardness test the shaft, so at least they know what to shoot for in the final product. Another issue is you usually get scale that ruins the precision ground diameters that ride on needle bearing (some transmissions) or need to be very precise diameter to accept a press-fit bearing. The shaft usually bends.

Grinding the surfaces undersize, building them up with hardchrome, regrinding and straightening are all possible, but unless your brother in law owns a grinding shop, bring your checkbook AND your Mastercard... you'll need both.

TomEV · 09-26-2008, 10:11 AM

For most DC traction motors, you are probably safe up to 5,000 RPM (if you can get them to that speed - some tend to self-limit to around 4,000 RPM). Some motors built for other applications are only meant for low speeds - say 2,000 RPM or so and may not be strong enough to handle the centrifugal forces from higher RPM.

If the motor is still in production, you may be able to find specs online. The DC series motor I have seems to be OK with continual 4,000 RPM, and I have had it to about 6,000 once (estimated).

Some AC traction motors can spin near 10,000 RPM, but check the specs for the particular motor.

Here is a link to a few motors that were 'oversped'...

Blown Commutators

bnjpiper · 10-19-2008, 06:35 AM

I had thought of the same type of project often. My idea was to connect the motor to the trans but power it only on acceleration any thing under say 1000 RPM or maybe 1500 RPM. Because the Electric Motor has full Torque from the get go. The optimum gas engine power is rated at X-RPM. So the trick would be to coordinate engine power on after the Electric Motor breaks the inertia where most of the fuel consumption occurs then cut the Electric motor Power off at that whatever RPM. I was thinking of using the biggest AC type electric engage disengage clutch so not to have to worry about the motor at higher RPM's. I currently have an old neon I'm considering using for my experiment.