Drop In Motor Converts Car To EV

With the latest craze of electric vehicles, it might be tempting to take an old project car and convert it from gas to electric. On the surface, it sounds simple, but the reality is there are a number of pitfalls. It would be nice if you could find a drop in engine replacement that was ready to go. According to Swindon Powertrain, you’ll be able to soon.

Based on their existing powertrain that can convert a Mini to EV, the transverse powertrain weighs 70 kg and if it can fit in a Mini, it can probably fit in nearly anything. Specifically, it’s 60 cm wide and 44 cm deep — that means it could fit easily in a roughly two foot box. The height can be as little as 28 cm. The company talks about fitting it on a quad bike or even a loading platform. It can be thought of as sort of an electric “crate engine” — a common term for a ready to install powerplant that, as the name implies, arrives in a crate.

The powertrain with a single-speed transmission, cooling system, and inverter weighs in at 154 pounds and generates up to 110 horsepower.  We aren’t sure what the expected battery pack is, but presumably, it will be somewhat flexible.

It’ll be interesting to see how people will integrate these if and when they become available as planned in June of next year. Can you drive a differential? Can you use two or four, each driving a different wheel? Turns out we might just be car designers after all.

If you want to see what they did with a Mini, look at their E Classic which claims an 80 MPH top speed and a range of 125 miles. We’ve looked at conversions before. If a conversion is not your thing, you could try to go Open Source although that project doesn’t seem very active.

42 thoughts on “Drop In Motor Converts Car To EV

    1. That can be (and is) perfectly legitimate. You’re allowed to register any ‘older than’ plate to a vehicle in the UK. A quick check on the government site shows that 218 RMU is registered to a red electric Austin of 1983 vintage.

      1. Problem is with the modifications to the car it’s likely going to need to go through a full SVA test, especially if they are producing a run of them.
        Since they are asking £79K for them each, I guess that means they are SVA tested, else all of them are going to be Q plated.

        To avoid SVA, 8 points are required from this list.

        Part Points
        Chassis, monocoque bodyshell (body and chassis as one unit) or frame – original or new and unmodified (direct from manufacturer) 5
        Suspension (front and back) – original 2
        Axles (both) – original 2
        Transmission – original 2
        Steering assembly – original 2
        Engine – original 1

        Engine and box are out, suspension will be different as will axles.
        Assuming they haven’t altered the chassis I make 7 points. 1 shy of no SVA.

  1. Q mini would be small for my tall, wide load. I didn’t bother. At about 102 K US my wallet isn’t heavy enough, even if the car, would fit me While recycling a used car may be greener, why not purchase a new electric,hybrid, or a lower emission ICE new car, with the money,and get what’s optional for this mini? The toggle switch panel; is far out though, although I would want the hi-beam switch located there.

    1. Have you actually checked if you fit in a mini?

      They’re surprisingly spacious – at least the originals were, not 100% sure about the new ones – you could easily fit a very tall guy in one.

  2. The hardest part of an EV build is the storage, not the motors. Most vehicles structural layouts can’t easily accommodate enough batteries without compromises such as center of gravity shifts.

  3. My son has swapped his 1997 Opel 2 door Corsa for my 1972 Mk1 ford escort rally car (he’s restoring with updated bits all over especially ocd over the engine) since he got dirt cheap a 4 door Opel 1998 and swapped the engine from his older 1997 Opel. So I have this front wheel drive 2 door Opel (Barina in Australia) with the gearbox and no petrol engine, perfect for a conversion.
    So I’m keen to put a novel type electric motor in the front which offers wide range of torque. I’ve been looking at variants of the homopolar motor design but, they are really power hungry though torque is immense (if you have the battery capacity) !
    Still looking around for doing the front end with maybe more than one type of motor, anyone else looked at designs for something like that ?

      1. Neato, will be looking at details, thanks.
        Will be looking up few more patents for parallel rotor low volt designs since I also want to make this demo model and have means to fabricate the motor from scratch, also want Mac volts at no more than 60 DC. So far all new motors prior art not novel since current supply in essence parallel per commutating segment, ie done to death nothing new though some slightly more interesting mounting or interleaving ideas not in their patent but in their drawings Lol, nice bonus :-)
        For sure will check out the leaf, where I am in Australia not many around so will ph the wreckers, cheers

  4. Rich man’s toy for virtue signalling.

    For that kind of money I can buy nice used econo box like a Volkswagen Jetta and have $70,000.00 left over. Or buy a much older car for a couple of grand and fix it up with a Duramax engine.

  5. Ooo, I wonder how much they will sell the power plant for – I’ve been wondering about doing a conversion on my kit-car and I see on their press release, in the sketched images, there’s a Lotus7-like car which, given its source for most kit-cars, is probably a good indicator that I could use it (although looking at the renders of the complete unit, I’m not sure if there’s quite enough space between the rear axle and the seat backs)

    1. There’s more space on yours than there would be in a Caterham (and you could claim a bit back from the ‘parcel shelf’ too – and loads of space under the bonnet for batteries. Go for it – and let us know how it goes…

    2. I’ve wondered about that same thing. I think a Chevy Volt battery pack would provide more than enough power for some horsing around. Not exactly a ton of range, but it’d still be an absolute hoot to drive.

  6. I don’t drive or know particularly much about cars, but if it’s at all similar to the way mechanical stuff in general seems to work, I suspect the in-wheel motors will be the big thing. eventually, and the one central engine thing will go away once it’s proven reliable enough.

    Redundancy, torque vectoring, and fewer gears seems like a good thing. Drive trains aren’t 100% efficient, and EVs are some of the most efficiency critical products out there, because every percent of waste is a measurable range reduction.

    1. Lot’s of extra complications with in-wheel motors (increased unsprung mass and difficult bearing setups for one). I doubt very much they will ever become a thing. Much easier to have a more conventional setup with a diff and drive axles from an ease of manufacture and maintenance perspective

      1. One “inboard motor” and a driveshaft for each wheel is an interesting setup. You don’t need a diff and can do fancy torque vectoring, you have the same unsprung mass as a single motor + diff for each axle (you can even put the brakes inboard as well for even less unsprung mass, better cooling and more complicated maintenance).
        IMO individual inboard motors is the best of both worlds, but slightly more complicated (not mentioning space and weight constrains).

        1. I’ve wondered how well a person could pack in some of those axial flux motors (e.g.: Magnax, YASA). They aren’t very wide at all, and the RPM range seems to closely match what you’d need for a direct drive.

    1. MPH is miles per hour

      A Mile is 8,448 bananas (a nautical mile is longer at 8,448 plantains).
      However, it’s defined at 1760 time the length of the monarch’s pace, which means that when QEII pops her clogs in a few years and is replaced by Charles, hitting the MPH efficiency thresholds will be come much harder for car manufacturers.

      An hour is 1/6570 of the time it takes for a banana to grow and ripen on the tree.
      The definition of an hour escapes me, but it’s somehow related to the movement of astronomical bodies.

      A pound is 2.5 bananas in weight, but it’s defined as the amount of flesh one must pay upon default on a loan in the UK.

      One Horsepower is the power required to raise a monkeysworth of bananas (16.5 bananas) by 1 degree Celcius per second, which is a perfectly obvious definition, not sure why you need to ask that one.

  7. @problemchild68 – Transferring an older plate (as a “vanity” plate) does not change the tax or MOT status of the car, that’s done on the actual build date on the V5. The government aren’t that stupid ;)

  8. I really liked the comments a few posts up about the wheel motors. I’ve actually been looking into this for a smart car I’m picking up cheap. The technology has matured and the power and reliably may be there for the diy crowd. Provided your donor is small and light enough. I’m seeing 5,8 and 12kw units that’s could peak to double that. So 48kw peak by doing both rear wheels (x2) is in the range of possible. $4k for the motors, controllers, pedal, guages, then $2k for batteries so $6k. I was spending close to this making ebikes.

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