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A Kit that converts a Classic Mini into 80kw electric Mini [pdf] (swindonpowertrain.com)
68 points by giuliomagnifico 21 days ago | hide | past | favorite | 90 comments

This is great and awesome to see, but the prices soon rack-up.

- Kit itself: 8,850

- 12 kwh battery pack: 16,000 (no indication on range)

- Motor-controller: 3,860

- Charger: 1,950

- coolant pump: 144

Total 30,804, or £36,964.8 inc tax

And that is before you add a donor vehicle (and other bells & whistles like LSD etc) and costs/time for removing old engine and putting right the "probably knackered" original body shell (and likely interior too). Call it £40k all in (min) assuming you get a good deal on a donor vehicle + repairs etc.

I know classic motoring is not about price or practicality, but just for the sake of comparison:

New nissan leaf: £26,845 inc tax

New Kia e-niro: £29,595 inc tax

New tesla 3: £40,490 inc tax

Suddenly a Model 3 doesn't look so outrageous.

£19,200 (inc 20% VAT) for a 12 kWh battery pack is especially outrageous.

That cost is actually in the ballpark for an ICE drivetrain swap using new parts and fully prefabricated fitment. Can be done much cheaper going with used parts from wrecked cars. Cheaper still if one has the resources to do their own fitment fabrication work.

It's nice though to see an outfit with the kind of reputation that Swindon has earned in ICE motorsports jumping into the EV game. This is bound to be a straightforward and high quality kit for those with the means and not the patience or ability to spend a year of weekends tinkering - that's a section of the EV conversion market that's always been missing.

For those who care about the cost and enjoy long tinkering projects, the hobbyist market's already been around for decades, and now the used production parts market is becoming well established.

> no indication on range

less than 30 miles at a guess. An optimized and integrated Model 3 has a 75kwh battery from memory, for comparison. This wont be optimized at all on anything with a vastly smaller battery. Still a fun project.

If you're building a kit for a production volume in the hundreds on up and no reason you couldn't scan a floor pan and then just take a "dozen cells here, hundred there" approach and interconnect it all as necessary. Considering the price point of the kit it kind of seems lazy not to do it.

>>"dozen cells here, hundred there" approach and interconnect it all as necessary.

Heat. You cannot just daisy chain batteries ad hoc wherever you find the space. These things produce heat. Too much and battery life will degrade rapidly. Much too much and fires start. And too little heat (drawing from frozen batteries) or inconsistent temperatures of batteries in the same circuit can cause all manner of nasty low-voltage surprises.

You are totally correct of course, a Tesla is the more practical and economical choice. But fun is the key word i think...

I suspect for many people that price is already considered well into luxury car territory (I've never bought a car >£5k, the used car market is large in the UK and the most common way people acquire cars)... Anyway my point is, 40k for most people is not an economical purchase, it's for fun - and even though I think Teslas are kinda cool - I find the idea of a raw EV powertrain in a classic like the mini quite appealing over all the distracting gismos and fairly normal looking modern car you get from a Tesla.

- takes cover, behind old mini -

and other bells & whistles like LSD etc

It would be dangerous to convert a car while you're on hallucinogens.

dangerous... or grooovy?

And the cops don't appreciate fish driving around, they frown on that.

Gotta be careful with those Lysergic acid differentials.

Pre-owned electric 2017 Fiat 500e with 20k miles: $7,000.00 on eBay

It will be interesting whether any of the electrical components (battery/charger/controller especially) will be able to be adaptable from budget-priced used EVs to power a kit like this.

Plenty of people still want a unique vehicle, and electrical drivetrains are a lot simpler than everything required for an ICE.

Used Tesla modules seems like a good fit for niche outfits like this.

E.g. https://eveurope.eu/en/product/tesla-model-s-module-53-kwhr-...

5.3 kWh @ EUR 1150 (ex VAT)

That's when you pick up the phone and offer 30% of sticker.

I'm from the future. We sell kits now that convert electric cars to "classic gas burners" and they're all the rage.

The catch is you have to spend an entire book trying to get a liter of "gas" and you can only drive the vehicle on the moon.

Why would you think they would allow that? The moon has been 100% electric cars for decades.

It also would be problematic to find the oxygen you need to burn the fuel.

I'm sure it will always be a community into ICE engines, but I am not sure it will be very big. The community of horse carriages isn't super big for example.

By the way, can you tell me how to make a good covid19 vaccine?

I doubt that this’ll happen.

Gasoline is only financially viable because of oil refinery at scale. Once electrification begins to take hold gasoline prices are going to suffer destabilizing swings as low demand drives prices down and bankrupt refineries drive prices up again. These swings are going to drive more consumers over to EVs for purely economic reasons, since at least an EV is price stable to charge.

Once it’s done I doubt there’ll be enough hobbyist gasoline users around to fund a single refinery, let alone any distribution mechanisms. What few refineries that survive will be retooled (at great cost) to produce either the precursors for plastics, or kerosene for aviation fuel. What few ICE vehicles that will continue to work will probably use something akin to biodiesel, something doable in your shed if you’re brave, but extremely rare overall.

I think you will be forever able to buy petrol, but at some stupid price. But enthusiasts are known to pay premium for their hobbies. Recently I watched a video about someone driving one of the original Benz "cars" in Germany, really, a 100 years old carriage with a single-piston engine - which is all fine, except that the engine runs on Ether Petroleum, which is only still produced for medical reasons.....so any time they want to pull it out of storage, they literally just buy several bottles out of a pharmacy.

Hell, as I mentioned in another comment - if you live in UK and are willing pay premium(like £5/litre) for it, you can still purchase leaded petrol for your classic vehicle which you stubbornly refuse to convert to regular unleaded because "collector value" is a thing.

> the engine runs on Ether Petroleum, which is only still produced for medical reasons.....so any time they want to pull it out of storage, they literally just buy several bottles out of a pharmacy

The first journey of any length in a motor car was made by Bertha Benz in her husband Karl's 1888. She bought her fuel at pharmacies...

Ha, full circle then.

Here's the video, if you're interested:


Why don’t they just buy 100LL avgas? Well under £2/litre, widely available, rubber compatible, and the shelf stability is extremely long.

The leaded petrol thing is especially dumb, as the only "modification" needed to convert a car to run on unleaded is retuning the carburetor.

Probably not so dumb if we're talking about a car that's over 100 years old and a priceless example shown in a museum or at car shows - modifying it in any way makes it well, not original any more. Also I'm not so sure these antique cars can be "just retuned".

Seems silly to pay so much for leaded fuel. I used to have a 1974 mini, and a single bottle of lead additive would last months.

> Once it’s done I doubt there’ll be enough hobbyist gasoline users around to fund a single refinery,

Not sure what you mean by "enough", but even if gasoline goes away you'll still be able to buy Avgas which should be useful in cars. Plus there is a ton of equipment out there that burns gas which will drive some demand. Generators, two stroke mowers and equipment.

There will be gas widely available for at least another 50 years. I do agree gas prices will go up quite a bit though. In particular, anywhere real estate is expensive gas stations will get driven out in favor of more profitable uses for the land.

The only thing you listed that isn’t well on its way to electrification is aviation. And even in that space I expect general aviation to electrify first, since it’ll suffer badly under the price swings I mentioned. Commercial aviation mostly uses kerosene, so my comment above still holds.

I’m actually in the market now for a lawn mower, and electric is price competitive once you factor in lifespan and maintenance costs. Plus I don’t have to deal with two stroke motors, which are awful things. I genuinely doubt that they’ll even sell gas lawn mowers by the end of this decade.

Had a longer post, but realized I was splitting hairs and arguing finer details. The big issue in question is how fast the cost of batteries will come down. If battery prices keep coming down at the current rate or accelerates, it's likely demand for gas will crash hard. When that happens is hard to guess.

> I genuinely doubt that they’ll even sell gas lawn mowers by the end of this decade.

Yeah, I have a DeWalt and love it. It does burn through batteries fast though. Fortunately I have a bunch of batteries for a lot of different tools.

FYI, I just switched from a battery electric mower to a manual reel mower because of shrinking battery capacity and expensive batteries. An extra battery costs well over 50% of a battery and mower together. I still have the mower, I just don't use it much anymore. I do use the battery powered strimmer/weed eater.

I've thought about bodging my own battery pack, but I don't want to burn down my house.

> FYI, I just switched from a battery electric mower to a manual reel mower because of shrinking battery capacity and expensive batteries. An extra battery costs well over 50% of a battery and mower together. I still have the mower, I just don't use it much anymore. I do use the battery powered strimmer/weed eater.

Yep. The only reason I find it viable is because I built up a big supply of compatible battery powered tools. Prices for batteries are coming down though, hopefully this will trickle down to tool batteries as well because I want a couple more batteries for my chainsaw and really can't put out $300 for them right now.

My neighbour still has sacks of coal delivered for her fireplaces every few months, something which has likely been going on at her address for over 100 years. There's so much stuff that uses gasoline I can't imagine it will stop being produced even if it becomes quite niche.

Unlike fireplaces, gasoline engines really don’t last that long. They also tend not to get into crashes very often.

The vast majority of gasoline engines that are produced typically last about a decade or two. While we all think about the hand full of beloved 1960s sports cars that are carefully maintained by their enthusiast owners, the median gasoline engine is installed in a Toyota Corolla and will be melted down 13-17 years after its first produced. If we start electrifying now, the vast majority of gasoline engines will simply age out of the population on their own. This will happen faster if the electric equivalent gets cheaper, or if my hypothesis about gasoline prices turns out to be true.

Might be a less extreme example, but look at retro gaming fans, e.g. a few of the Sega Saturn nuts I know in the homebrew community will actually pay $400-800 for a single game that was originally $70-80: (I'm seeing $1175.47 here for a new copy) https://www.pricecharting.com/game/sega-saturn/panzer-dragoo...

People will pay a premium to replicate an experience.

This has nothing to do with gaming, its pure speculation.

There will likely still be significant military & other 'off-grid' demand for liquid fuels into the indefinite future.

A lot of that will either be kerosene or feedstock based diesel compatible fuel; not stuff you’ll be able to feed your classic BMW.

In general though a lot of “off grid” stuff is going to heavily prefer solar + batteries where possible, since it’s much easier to keep that running without having to constantly go into town for supplies.

Don't see much demand for hay from military.

Coldstream Guards must get through a bit.


What about the British Army - it has more horses than tanks!

Horse carriages are almost carbon free, reasonably priced and require a horse. A horse might eat 10 to 20kg of feed a day?

Selling my car lads. Ya boi getting a horse!

I’m big into ICE. I have a srt and a ls1 flyin miata.

Any idea on pricing, anyone?

We need more of these 'drop in' style conversion kits. If only to keep classic cars on the road.

I can't see BigCar Co. being happy though, they are having enough trouble selling new cars as it is, and even worse luck trying to sell [overly expensive] new EV cars, without people converting their favorite small cars to electric.

I can't imagine classic cars will ever be banned, just like we have never banned horse carriages off our roads. The environmental impact of someone driving their ICE classic once in a blue moon is absolute zero.

Hell, some places(UK!) still sell leaded(!!!) petrol specifically for use in classic unmodified vehicles. It never got completely banned because the impact of someone taking a 100 year old carriage for a drive and burning couple litres of leaded petrol is absolutely not worth worrying about. Last I checked there were still 3 companies in UK authorized to sell it.

Politicians ban irrelevant things all the time because the number of people pissed off is small compared to the number of virtue points scored.

Hard for something to score “virtue points” if it isn’t, at least in some respect, virtuous.

It's gradually getting to the point that petrol vehicles with lower mileage are becoming less practical because petrol stations are being torn down, so that refuelling requires larger detours.

It's one thing pleasure-driving and keeping a can of fuel around to keep it going. Needing to spend 20% of your fuel on getting fuel - and then being forced to queue either inside the shop to pay, or outside on the forecourt - is what kills a vehicle for commuting.

You can also buy lead replacement fuel additives [1] designed to run leaded-fuel cars on (widely available) unleaded fuel.

[1] https://www.holtsauto.com/redex/products/lead-replacement-mu...

I do remember reading that those don't work these super old engines though, they require either actual leaded fuel or a modification to the ignition system. But yes, for more modern cars you can just get the anti-knock additive.

Edit: Yep, I had to look it up - certain metals used in old engines make them incompatible with common additives. You can however, buy an additive( Tetraboost (Tetra-ethyl lead)) that contains lead, effectively making any unleaded petrol equivalent to leaded petrol:


There seems to be a total of 13 garages in the UK authorized to continue stocking actual, real leaded petrol.

Tetra ethyl lead is what makes leaded gas leaded.

I wish there was a drop-in kit that could turn any car into a micro-hybrid by running all electric loads off a li-ion until dead, then switching to the lead-acid system.

Electric loads are like 10% of a car’s use, and here I am burning gas extremely inefficiently to kill my alternator to generate it.

And more stuff is becoming electric instead of belt drive (e.g. cooling pumps and power steering pump).

If my average trip is 50 miles, being able to shunt all electric loads to a supplemental li-ion battery does just as much good as having a hybrid plug-in drivetrain that can do 5 miles engine-off.

Not quite, but I think we’re missing a huge opportunity to turn entire fleets into 5%-10% electrics.

Would be cool if my alternator could be used for some regen, (new automatics are doing engine-braking!) but that’s probably outside of the scope of a drop-in kit.

I think a battery sufficient to realistically replace alternator output would be too large and expensive.

Car alternator output is on the order of 1 to 2kW. A battery [1] which can do ~1kWh - 100A at 12V - is about $300 and weighs 12kg. It's also big - 40x20x25cm - stick it in your boot and you'll notice the space reduction.

That would just do 1 hour, at the lowest level of alternator output. If you need more power or more range, double it; more of both, double it again.

The next question to ask is do you trust keeping a $300 Chinese battery in your car without it blowing up? You probably want a reseller who'll stand behind their products, ensure the supply chain maintains quality, has sufficient safeguards, etc. The price is going to go up even more.

[1] https://www.alibaba.com/product-detail/1KWH-Deep-Cycle-LiFeP...

Most cars are commuter driven and 1-occupant (if my highway commuter experience is to be believed).

This wouldn’t physically replace the alternator, just let it free-spin until drained.

The economics are already confirmed (or not?) by the presence of plug-in electrics, it’s just that they go engine-off for some miles, while this idea goes engine 90% for 10x the distance. It’s perhaps even more efficient to make electric loads fully electric instead of building an electric drive-train onto an ICE one.

Chevy is doing something along these lines, so maybe not too worried.


The pricing is in the post - 8850 gbp + vat. That’s not including the batteries, esc, charger, or dc/dc converter, just the motor and mount kit.

One small part also left out of the pricing: the car, which was not necessarily acquired for free.

I re-read the PDF. Pricing is right there. Doh!

I'm interested to know as well

I've had a lot of Minis in just about all possible shapes and sizes. I've rebuilt them from the ground up, done a lot of chassis work on them and made them go a lot faster than they originally were designed to.

The classic mini is a work of art. You can do just about anything with it. But the balancing act between weight, handling, size and power is a delicate one.

Adding batteries and an electric motor is for sure going to upset that balance in ways that you will not enjoy as much as you may think and I suggest that before you embark on a project like this to find one and drive it first, to see if it is something that you will like once it is done.

Another thing to keep in mind is that Mini's are notoriously hard sprung and that you're going to have a hard time getting it to handle safely. Personally I'd pick another platform, if you want to go vintage try a Citroen DS or a VW Beetle. Slightly more room to play with, especially the beetle is a breeze with the rear wheel drive drive-train.

It will also end up being a lot more reliable and probably cheaper too because you won't have to miniaturize everything and getting rid of excess heat will be a lot easier.

Finally, note that in most countries this is not going to be road legal, in the UK it can be done but elsewhere you are going to have to go through a very expensive test regime in order to get certified.

80kw is 107 horsepower. It has a peak of 120kw which is 161 hp. For comparison, the engine in a classic mini is 40hp or less.

I’m not super involved in the mini scene, but own a classic Beetle. These old cars are super lightweight, so 40-60hp is pretty peppy as it is (although top speed is limited due to the 4 speed transmissions). 107 hp is gonna be crazy in a mini.

I've got over 90hp in my modified 1275 S road engine and Swiftune can build you one around 125hp (https://swiftune.com/engine-building/competition-engines-his...). A highly modified classic mini is a visceral experience, even when operating within the speed limit and especially on 10 inch wheels. Excuse me I have to go for a drive..... I also have a clubman shell I want to do something with, vtec, motorcycle or electric? hmmmmm

> A highly modified classic mini is a visceral experience, even when operating within the speed limit and especially on 10 inch wheels.

A stock 1000cc with nothing more than a tweaked cam profile plus LCB exhaust was equally exhilarating when I had it 20+ years ago. Loved that car. Didn't love the drum brakes and scary-fade-going-downhill as much though!

Properly envious that you still have a functioning 1275 - expecially an S (if you mean Cooper S?) and not just the GT.

Yeah its an Australian Cooper S, I got it in 96. To be honest the tech really hasn't changed that much since. I suppose the electronic ignition is the biggest change and I changed to an HIF carb - modded to vizard spec of course. The clubman 998 I have is drum all around, and I agree! The only saving grace is due to their narrow width you can hopefully squeeze between cars waiting at the intersection when they inevitably fail.

I learned to drive in a Mini Mark IV. After passing my test I had all sorts of near misses with it. One particularly hairy one was coming round a bend to find traffic queuing at a junction, I locked the wheels and hit the curb, spinning 180 and finishing inches from a wall, no damage.

That's a neat little machine you have there!

90 hp in a mini that weighs just over 600 kg is going to move like a rocket. Make sure you upgrade the brakes as well! You can fit double caliper ones they have a lot more bite to them.

180HP Honda engine swap will cost less than this conversion kit alone.



> These old cars are super lightweight, so 40-60hp is pretty peppy as it is (although top speed is limited due to the 4 speed transmissions). 107 hp is gonna be crazy in a mini.

Yes! Also, if you've ever driven one of these things you will know how low to the ground they are... it's not the same as some silly lowered hatchback, the whole thing is _tiny_ compared to modern cars, so 60mph feels you are breaking some kind of ground speed record.

This will be a crazy fun car... I will kinda miss the manual transmission - I guess i'm getting old.

Haha you beat me to it by a minute. I assume the battery etc. will add some weight and that will partially offset, but still a 107hp classic mini sounds pretty fun!

That’s true about the battery, but being such a light car I bet you’d only need a ~20kwh battery pack like in a Volt and still get usable range. That battery gives the Volt 53 mi of range, and that car’s much heavier. It’s under 500 lbs, and is pretty common to use in these EV conversions.

Classic Mini engines were available from the factory in substantially higher power ranges:


Is it possible to get a rough idea of the new top speed of it, from the horsepower?

I'll make a wild bet... 90 mph, gearing-limited.

It's still an aerodynamic disaster, and whilst you could put a higher gear ratio in, why would you?

But maybe less fun because of the weight.

Anyone interested in EV conversions should definitely check out Open Inverter Forum [0]. Conversions can pretty easily be done for a very reasonable cost. There have been 500 eur and the like conversions incl batteries. Toyota/Lexus hybrid drivetrains are very cheap and plentiful and make great conversions. Same goes for Nissan Leaf and Tesla motors. Lots of options for batteries as well for much more reasonable prices if you’re willing to scour.

My own project is a Lexus GS450h hybrid that I bought with a broken ICE for very cheap. The two electric motors in the hybrid transmission are capable of about 220kW. And there’s little to be modified at the car besides de-ice-ing and adding batteries.

[0] - https://openinverter.org/forum/

Rich Rebuilds is electrifying a blown up late model Mini - https://www.youtube.com/watch?v=ykToLuUghhk&list=PLHgCeKJSmJ...

Anyone interested in this sort of thing should check out diyelectriccar.com. In particular, this thread follows someone converting a classic Mini into an electric using parts from a wrecked Leaf: https://www.diyelectriccar.com/threads/nissan-leaf-into-rove....

I think it's obviously not as cost effective as buying a standard electric car but still seems like a challenging and fun project.

£10,620.00 for the motor alone. 16k GBP on top of that if you want a battery as well. Then the other electronics, charging, motor controller.. 30k easily. Seems pricey.

These guys here (the workshop is in Wales):


are also making a TV show called "Vintage Voltage":


do this kind of conversions and seemingly also sell parts.

That's pretty light on details, and the more I look around their site, the less I seem to understand about what the kit actually includes, or does, or how much ancillary equipment has to be created by the builder.

We need one of those for the millions of VW Beetles around Latin America.

EV West in California does great work on classic kits.


VW themselves announced that as they ramp up battery production selling official EV conversion kits for classic Beetles and Minibuses was something they very much want to support: https://www.theverge.com/2019/9/5/20851784/vw-beetle-electri...

They exist. I've seen a converted classic beetle in person up in Canada at a car show. I wish I still had the pics of it.

Thats 80kw power, 12kwh battery. Does't say what the range will be. So the Classic Mini is small but with 12kwh I can't see getting more than 100miles

100 miles? I have a 11.6kWh battery in my Volvo and it's barely enough for 30 miles. Even with the mini being a lot smaller and lighter I can't imagine it hitting 50miles.

Yeah a complete guess on my part. Classic minis really are tiny though

interesting... I would like to convert my old Nissan Micra, but the legislation on Spain it's so problematic that actually I can't do. I hope that we copy from France on this...

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