[Baxter]

Good morning new friends. I've been kicking this idea around for awhile and now I'm here to ask the experts if my idea is feasible. Keep in mind, I'm a decent shade tree mechanic, have built a couple engines and even an automatic transmission but still consider myself pretty green in the overall scheme. I have ZERO knowledge of electric motors and electricity in general but I'm willing to learn. Here's the skinny-


I have a 1981 VW Rabbit 1.6 n/a diesel I've been driving for the past few years. The whole time I've been using a 50/50 blend of diesel and WVO. I average 45 mpg. I have about a 20 mile trip to town, 90% highway.


My plan isn't to totally convert to electric but rather make a hybrid. I would use the diesel engine to drive to town, then use electric in town. I would be happy with a top speed of 40mph but faster is always better.


Obviously the Rabbit is front wheel drive, the rear wheels are just back there, doing nothing, just rolling. My idea is to install an electric motor to drive one or both, OR a pair of motors to drive both wheels, depending on your guy's recommendations. Seems to me a (insert correct term here) motor, with a shaft going all the way through it, mounted in the center rear of the Rabbit with a couple of cv shafts going to each wheel would be the cleanest install.


The car is a real piece of crap and I have a parts car as well so I'm not too worried about cutting stuff up or whether or not I'll ruin it in the process!


I'll admit, I have done very little research, but it appears with the right motor selection I probably won't need a transmission, especially with my goal of 40mph. I was also planning to use 4-6 12V batteries to power the motor.


A couple things I'm worried about-


With the motor(s) connected, what will I see when I'm using the diesel engine going down the highway? Will it create a major drag? Will I over-speed the motor(s)? If so, I can always create a way to disconnect the cv shafts if I have to, not that I want to.


Actually I guess that's all I'm worried about right now!


I have manual steering, manual.. everything really so I'm not worried about driving around in town with the engine not running, transmission in neutral.


Go easy on me, but please dissect my plan and give me some pointers. If it sounds like it may work, this will probably be my build thread.


Thanks guys.

 

[Baxter]

https://www.ebay.com/itm/MARATHON-E...851581?hash=item4686987ebd:g:NYwAAOSwpwZbsqF8

EH? EH? Is this even powerful enough? Getting heavy already, not to mention the weight of the batteries. If I go this route I'll definitely have to beef up the rear suspension.

 

[Baxter]

[/QUOTE=brian_;1022523]
This configuration is frequently proposed in this forum, although of course you're unlikely to stumble across the discussions so you wouldn't be aware of them. I just spent a few minutes looking for them, and haven't found one yet.

This scheme has lots of problems, and no one actually completes a project with this design. For a start, do you understand how to add a drive axle to a hub which isn't normally driven? After you install the rear motor and reduction gearing and motor controller and batteries, do you still have space for the fuel tank?

On a more fundamental level of what this hybrid is supposed to be, how does the battery get charged? Is it just a very heavy way to get an extremely short electric-only range with energy that you get by plugging it into a charger while parked?[/QUOTE]

I do realize I'll have to make the hubs drive hubs, was going to look at the front hubs to see about adapting, if possible. My plan was to try to fit the motor in the spare tire compartment, batteries on top/side of the motor. Haven't looked at where the fuel tank is... My plan was to charge the batteries with an outlet, at least at first but I'm going to assume you're right about the short range.

Thank you for the links, I have some reading to do and you told me exactly what I wanted to know, doesn't sound... practical. Thank you very much for the insight.

 

[Baxter]

Thanks you guys. While this project doesn't look like it will go much further, I am going to hang around for awhile and maybe learn some stuff!

 

[Baxter]

Okay don't take me seriously, BUT! Looking at something like a Chevette rear end to fit under the Rabbit. Might take quite a bit of fabrication but it would take care of the biggest issue.. Has the same bolt pattern too! Just kicking the idea around still, no real plans.

 

[Baxter]

Can I first say, thank you so much for challenging my ideas without being a total jerk about it. That's really a breath of fresh air compared to most people on the interwebs.

What I was thinking was mounting the motor above the axle and driving it with a chain or something. Unfortunately the Chevette rear axle is a little different having like torque tube thing that's a couple feet long looks like. Hopefully I can do away with it somehow.

And to think I scrapped one and sold another one for a derby car a few years ago..