Rear wheal\3weal drive hybread. Meto LSI

[supernerdboy]

Ok so my car is not working and is pending parts and a good fuel injection troubleshoot. Also I work at a scrap yard that recently got in an electric forklift. (I think you know were this is going) anyway I was thinking of ways to make it drive with just electric power, but did not want to remove the engine (well maybe) so I can still take road trips. So I have a two way choice, A:change the motor to an electric one and use a generator to power it on long trips. Pros lighter, Cons slower, and may not save much gas on a long trip. B:Make the forklift motor turn the rear axle. I think this might be hard to do. Mr. "Jimmy Rig" knows a trick or two, JK. So I got the idea to turn just one wheal, with a belt. I have attached a drawing for reference. My main concerns are. is the belt going to stay on, were do I get a lug with extenders like on my drawing, how do I gear it, how fast will it go, and is this a good idea. I do not like the idea of spending money on the controller, so perhaps I could use battery bank switching large resister switching, or just plain on off on off to control my speed. Any suggestions thought welcomed. Thank you. Diagram of me in two months I was almost thinking yay attachments, but then, only 23k, photobucket time.



By the way I almost forgot to mention it is a metro lsi 4 door 94 hatch back, I have stripped the front right and back seats and almost all the trim from inside. Soon I will strip carped and fenders (do police in Texas mind no fenders no bumpers and is this ok on FE? I want to lower the weight, then mod aero later) ok. Goodnight.

[Ryland]

You will most likely get a ticket for not having fenders and for sure for not having bumpers.

Also your motor is going to have enough torque that it will most likely snap all 4 lugs off at the same time unless you have something really ridged behind the pully when a wheel is bolted to a hub it's the sheer on the lugs that they are resisting but in your set up you will be bending the lugs, snapping them, also all of the energy is going to one wheel at that point, with extra vehicle weight and... this is just seeming like a bad idea that is going to cut back on the number of Geo Metros that are on the road.
If you really want an electric rear wheel drive geo metro then I would say find the rear drive axle from a subaru justy, Honda wagovan, toyota corrola or some other small car that had a 4 wheel drive version back in the '80's.

[Patrick]

This has been done before and it seemed to work.

I think you meant 48, 72, and 96V for your batteries. The problem with that setup is that the 48V batts will be discharged more than the 72s and the 72s more than the 96s. But you could rotate them after a while so they all "wear out" at about the same time. Make sure your switch is rated to carry the current and voltage you will be using.

Taking the fenders off would be terrible for aero. Don't do it unless you won't go over 30 mph.

[Ryland]

closing a switch with 48v going to a motor in a vehicle that is not moving would be kind of like dropping the clutch with your car in 2nd gear and the engine revved up to about 3,000rpm, you will most likely draw over 500 amps for a second or more and if your "switch" can not handle it, it will not just melt but it will burn the contacts, creating a cloud of smoke of vaporized metals.
My 1,400 pound electric car used to have a contactor speed controller, it would rewire the battery packs for different voltages to give the full range of speeds, 48v being the fastest speed (40mph) and if you did not use the first two speeds to get moving up to at least 10mph (15-20mph was better) the full 48 volts would lunge the car forward, over the past few years I managed to snap leaf springs on the drive axle, vaporize the leads coming off the carbon motor brushes and vaporize a 3/16" by 1/2" copper bar in one of the contactors because there was a fine layer of dust on it's dime sized silver contact.

This is why solid state speed controllers are so nice, high speed switching allows for a nice smooth acceleration while keeping all of your batteries discharging at the same time giving you greater range, otherwise your range is only as good as your first bank of batteries.

[Frank Lee]

I can see the appeal of a simple switch controller as it doesn't have the efficiency losses...

[Ryland]

Originally Posted by Frank Lee

I can see the appeal of a simple switch controller as it doesn't have the efficiency losses...

A solid state speed controller tho allows the whole pack to be wired at a higher voltage, to get the same number of watts out of a higher voltage pack you don't have to draw as many amps, so right there you can use smaller gauge wire and often times the pre controller increase in efficiency makes up for the losses inside the speed controller, the batteries also see gentler use so they last longer as well, I've had my solid state speed controller installed for about two weeks now and even tho my batteries are a year older then they were last year my state of charge when I reach work is higher then at any point last year and I don't feel like my motor is trying to rip my car in half any more.

[Patrick]

Dave Cloud's Dolphin.

[Ryland]

Yep, Dave Cloud's has two motors so each motor is moving less weight forward then the geo metro would weigh if you pulled the engine, fenders and bumpers off and tried to power it with a single motor, he also has a solid state speed controller for each motor and I am going to bet that his spacer for that sprocket is a solid spacer, not long bolts that thread in to the tops of drilled out lug nuts.

Like I already said, the design as posted in this thread would be kind of like revving your engine up to 3,000rpm and dropping the clutch, if that is how you drive all the time then you are going to end up braking a lot of parts and if you are trying to move an entire car with a single drive wheel with a pulley that is dangling off the tips of some bolts so it clears the tire then when you apply that power someone is going to get hurt and people doing stupid stuff that gets them hurt or killed is why we have so many laws.

[Frank Lee]

The pulley mounting is easily solved.

[Ryland]

Originally Posted by Frank Lee

The pulley mounting is easily solved.

Yes, it is easily solved, but I'd rather see it work the first time, then have the project delayed because of repeated trips to the emergency room, or become something broke and mangled the car beyond further use.