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Drop in electric EV motor retrofit for older cars?

I just came across this link and this seems like a neat idea but I am sure it will be harder in practice than the article makes it sound.

I wonder if you will have to specify the model of your car and they will send you mounting brackets made just for your car to make it fit. Many car radios are “universal fit” and come with the appropriate brackets, harness adapters, etc. that you specify upon their purchase.

Either way, this sounds like a neat idea and would be nice if they could make it work for not a ton of money.

I’d guess you are on your own for brackets ad such to make it fit your car. If you have a popular car, companies will make kits for them. That '58 Edsel, well, you are on your own!

That 58 Edsel gets a 390 or 428 under the 332 valve covers, or a 430 under the 361 valve covers.

Well like they say if you want a classic car restored, buy one that is already done and you’ll save a lot of money. I’m not sure there is much of a market though for electric classics. Maybe they have a sound system to simulate the motor rumble.

I’ll be curious to see one that isn’t a computer drawing, and how they handle the power takeoff. Batteries are the tougher problem to me.

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Yeah it would be interesting to see what the value of a 58 Impala would be after someone hacked in an electric motor. Think of the business model. You want to save gas on a classic that you just paid $60,000 for? And what $20,000 to put a GE motor in it? To save what, maybe $75 a year if you drive it a lot. Like the old show on TV, Hee Haw.

I doubt that anyone would want to install an electric power powertrain into a valuable restored classic car but there are millions of other cars out there that can be modified. Wouldn’t your beloved Morris benefit from an electric conversion? Or is it all about saving a dollar on gasoline?

How about a compact car with a good body but a blown motor? Maybe an older California or Arizona car where they don’t coat the roads with corrosive deicing chemicals. Most older cars from colder climates are rusting out by the time a motor swap is required.

It would make for a nice car to run around town but probably would be a no-go over long distances. I would love to have an EV but wouldn’t work for my uses and climate.

A powerful electric motor electric motor would easily fit in place of any engine and transmission. But where on a convectional car are you going to find room for a battery pack of a size to give you decent range and how do you deal with the weight?

Stupid idea in my opinion/

I think most people put Datsun engines in them. To characterize it as “beloved” is a little strong though. More like an Ex girlfriend. I fully sympathized with the guy that bought it though and threatened to kill me. My only defense was that I told him everything that was wrong with it. What he paid for it was simply a small down payment to what was ahead for him. We all would have been better off to simply push it in the lake.


I have seen a Porsche 912 (the 4 cyl 911) modified with a Curtis controller from an electric forklift installed so I could see it. I didn’t get to talk to the owner but I’d assume a forklift motor as well. Batteries could be placed behind the seats and in the front boot where the gas tank used to reside but they were totally hidden.

Outwardly the car looked stock. For a car to take to cruise-ins and cars and coffee, it was perfect.

None of this is about saving money. None of this is about the value of an appreciating classic. This is all about building the car floating around in your head simply because you want to build it.

The combo that the Jalopnik article mentions is clearly . . . in my opinion . . . meant for vehicles that use an engine mated directly to a transaxle

So it should be more challenging to drop that in a vehicle that had a conventional layout with engine in the front and drive axle in the rear, such as your typical rwd pickup truck

But it should be a “drop in” for a fwd car or even a small sports car with mid-engine layout or rear engine layout. So a Fiero, Corolla, MR2 or 914 would be ideal candidates for this thing

What about that battery . . . I guess that’s the builder’s problem

I agree with @Mustangman . . . this meant for somebody who takes pride in his one-off and then can say “I did it”

What would happen if you actually dropped an electric motor in a car that was supposed to get a tailpipe smog test?

How would you register the vehicle?

What would happen when the notice for “smog inspection due” arrived in the mail?

I imagine you’d have to get the bar referee involved at some point . . . ?

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In California, I’d guess it shouldn’t be too terribly hard to register an EV conversion. I think they’d be pleased with the conversion. In states with no tailpipe inspection… I can’t see any problem.

The Morris Minor. In 1981 we were doing Northern boarder surveillance from Fairchild Air Force Base Spokane, Washington. Some of us got a weekend off and were flown to McCord AFB. While visiting The Tacoma, WA mall I found a very interesting vehicle on display. An MGA roadster EV! Of course it was not a practical street machine. It ran 1/4 miles at drag strips It was exhibition only as there was no NHRA EV class. It seemed to have the MGA stock body but the rear wheel wells were “tubbed” with 12 inch wide slicks. The EV drivetrain was 1981 crude. Six 12 volt automobile batteries in the engine compartment. Of course no transmission. The rear differential was replaced by a powerful electric motor. It could run a quarter mile in the low 12 seconds! I am not an electrician much less an electrical engineer. I really have no idea how this was achieved.

Forklifts used DC motors back then. A drag racer doesn’t have to be very “gentle” with the car. It is pretty much all or nothing. An excellent forklift engineer told me once - current makes torque, voltage makes speed.

A contactor array - basically BIG relays - can be created to hit the motor with a lower voltage, say 48V volts with a parallel strings of 4 12 volt batteries (or 8 - 6 volt batts) for launch. After launch you would shift into “high gear” a second set of contactors arranged to build 96 volts from paired-strings of 2 sets of 4 12V batteries for a high trap speed. That would be a crude but effective way of building your drag car.

Let them do an emissions inspection. What will they do when there are no emissions?

I would bet CA and other states would allow for this. The one issue I have heard about is taxation for the roads. Gas taxes pay for roads and these don’t use gas. They will care more about this. I guess some states have started ways of taxing electric and high efficiency vehicles.

Crude but arguably not very effective. That would be akin to lighting a fuse with the lack of any control on the power being delivered. You might be going through $2000 motors sending your bank account rocketing to the basement faster than the car! Controlling the slew rate on the power to the motor is very important to longevity as well as limiting the rpms and current/power to within specifications. None of which can be done by applying full pack power through contactors. You could build your own IGBT based PWM controller for not a whole lot of money if you have the skills to design and manufacture it. Maybe even less than the fairly expensive contactors needed to repeatedly supply 1000+ amps. Then a throttle control input and tach feedback at a minimum. A means to eliminate heat from the power electronics would involve a small exchanger, coolant tank and a pump to circulate it would help it survive longer period use than say a drag run.

I’ll certainly man the video camera for the rocket lighting ceremony however!


Now yer gittin’ all NEW school on us! I DID say “crude” :wink:

Yes, controller based system would be WAY more controllable and that is the tool the current crop (pun intended) of EV racers use get the job done. There are losses making heat in the controls, as you point out.

But a 12 second drag car isn’t all that fast and a decent set of drag slicks would hook up the “fuse lighting” contactor engagement pretty well. As for motor heat, it only has to take it for 12 seconds so a bit of over-max-current-spec would be possible for short periods. Might also need an “idle speed” setting to get it back to the staging lanes.

There are companies that do this today…but it’s expensive.

Other companies are out there that do it also…and a lot cheaper.

Yeah, we have some control topologies that are far more efficient than a PWM in our arsenal. Achieving 90% or higher efficiencies is not out of the question but becomes a more involved design exercise with less variability in the application. Using SiC devices also helps but they are pricey…

Oh, you’re talking about a 12 second car… why bother? :stuck_out_tongue_winking_eye:
Instead of blistering acceleration, the excitement will come in the form of melting electronics or exploding battery packs then…

I like your binary gas pedal switch just to make parking it more interesting…Hold my beer and watch this!

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