DIY Electric Car Forums banner

Grant electric mini.

159K views 311 replies 31 participants last post by  Studebaker 
#1 · (Edited)
Hi lads.

So, I decided to attempt this project.












. Yeap …it’s a mini. Not the best example, this one. In need of full restoration. That’s way this isn’t gonna be one of those fast moving threads. Although , I will work on electric drive train, along with restoration, so I hope I’ll have something to show for soon enough.

Mini isn’t the easiest one to convert. This transmission in the sump stuff makes it really difficult. I should probably have chosen different car. Say, Nissan Micra. Or Toyota Yaris. Or…but hey, if I am to part with 10k Euro plus in the course of this build, I’m not putting me dough into something that I can only drive while wearing balaclava. I don’t want a car that I have to park two blocks away from meeting place just to avoid being seen in it.

Mini on other hand, is a pretty little thing. Nice little car. And, if it wasn’t for that strangely designed drive train, I’d say it would be an ideal base for EV conversion. It is light, it’s simple, and it’s cool.

Mini it is, then.

My plan is to use preferably off the shelf parts, and components. New ones. Where not possible, those easily available. Scaling engineering and fabricating work down to the very minimum. The idea is to work out a way of converting these cars without complicated machining work, without difficult fabrications i.e. Can spent up to 10k Euro. That’s only conversion. Excluding car and its restoration costs. Anything above 10k Euro mark doesn’t actually make much sense for me. I don’t care for environment Neither I’m into saving the planet crap. I want the return of my investment during few years of using the car as daily commuter.

I’d like, driving this car wouldn’t require any special skills. That it could be driven by anyone. My teenage daughter, my partner (she doesn’t drive stick), and also my nearly 90 years old grandma. My grandma hardly even walks, to be honest. Let alone drive. But you know what I’m getting at here. Tricky clutch less gear shifting is out of question. Any gear shifting - for that matter- is out of question.

Car will be mainly used for commuting to work. I live in rural area (25KM from nearest town), and my partner drives to work 5 days a week. She does from 52 to 60 (depends on her shopping frenzy) kilometers there and back. And that basically covers our transportation needs.

I’m gonna start from the drive train. And here I could really use your help. Any advice, any suggestions, will be most appreciated. Actually, trying to figure out how to transfer power from electric motor to mini’s wheels - without getting into advanced engineering stuff - is the reason I’ve lost sleep lately.
 
See less See more
4
#4 ·
Not Irish. But living in Ireland. Small place in the middle of nowhere in county Tipperary.

Actually it was you Damien who infected me with the idea. Been watching you building your beemer and it got me hooked.

Yeah that’s what I’m thinking. Small fwd transmission. But in my case it has to be an automatic one. See it’s not me who will be driving this car. I don’t get into a car unless it’s absolutely necessary. And me woman doesn’t have a clue how to change the gear.

I been cracking my heed around CVT tranny from Micra. Older Micra. Plenty of those around. The thing is that its control unit would have to be modified, to work with electric motor and I’m not sure I’m up to the task here. But I probably try this route.
 
#3 ·
Hi,
You mentioned not wanting to use gears. Have you considered direct drive?

I'd be tempted to mount an oversize motor directly to a differential on the rear axle.

You can then control take off torque/speed in the controller (ramp rate?)

Cheers,

Mike
 
#5 · (Edited)
The trouble is, it’s FWD car. Oversized motor may also be tricky to fit. Mini’s engine bay is a size of larger watermelon. I was thinking about 9” kostov. Or one of those



Yes, direct drive could be the way to go, I guess. If CVT won’t play out, I probably attempt to fabricate a direct drive transaxle. Came across something like this



It’s drive train from berlingo electrique. Smartly designed I should say, but way beyond my engineering skills
 
#6 ·
You could use two of the Agni motors, one for each wheel but will need a reduction gear, chain or belt to get usable torque.

The Berlingo unit is nice but you will need the controller to go with it as it is a high voltage SepEx unit. There are some Berlingos being broken in Kent IIRC. The breaker isn't allowed to sell them on as vehicles but could be persuaded to sell the front half, which is the half that has all the useful bits. You would need someone who knows them though to make sure you are not missing any of the many hard to get components.

I would be tempted to just use an auto transaxle from something small and just go with it. A pre electronically managed car would be the easiest I suspect.

Alternatively, you could get a chain drive diff unit as used on motorbike-trike conversions. That will give you a wide range of chain or belt drive ratios for direct drive from one motor.
I know of a chap with the same set up in a mini/2CV based clown car he uses for children's shows.
 
#9 ·
You could use two of the Agni motors, one for each wheel but will need a reduction gear, chain or belt to get usable torque.
Somehow I don’t like the idea of using chain or belt to propel a car. Don’t know why. I’ve seen Malcolm”s dual drive power train in mini’s sub frame and it is very nicely put together, but …nah, no chains for me.

There are some Berlingos being broken in Kent IIRC.
I also found berlingo in Ireland. 3k euro asking price. In decent condition. Don’t know. Seems like kicking down an open door. Braking up good car to build a different one? Why not get and drive berlingo in the first place?

I would be tempted to just use an auto transaxle from something small and just go with it.
Small auto. This idea is most appealing. Say, there's that cvt transmission from Micra K11 a was looking at. It has electromagnetic clutch witch I would scrap, and couple transmission with motor directly. CVT doesn’t have to idle to be operational. Now, the pulleys that change ratios are pushed together or spread apart by hydraulics operated by set of valves. And here the troubles start. The valves are hooked to ECU. Do you think there could be the way of controlling those valves skipping the ECU ?
 
#7 ·
Glad to have been an inspiration:) My 2 cents would be this : Keep it simple. Sure , lots of interesting things can be done with enough time , effort and money but sometimes the best solution is the simple one. Also i would not go direct drive. It sounds great and works out great on paper but you end up with a milk float or a cooked motor.

I wouldn't be so quick to give up on the mini gearbox. Been years since I worked on one but it should be possible. As woodsmith suggested a small , non electronic automatic might be another good choice.
 
#10 ·
I wouldn't be so quick to give up on the mini gearbox. Been years since I worked on one but it should be possible. .
Actually this mini is an automatic. But, how to hook the motor to a gearbox where the gearbox is actually a sump? Seen it done thou. Metal plate bolted to the top. Then motor to it, chained up with a layshaft. Can’t say I liked it.
 
#8 ·
#12 ·
Hi Studebaker,
Like you say, the mini is ideal in many ways, but challenging in others. I think your conversion goals are spot on.
So you want simple, but no chains, belts or manual gearbox. It sounds to me like Caspar's Think solution is the best fit. It's neat, reliable and should involve the minimum of machining and fabrication.

Having said that, if I was starting again and didn't already have a couple of cheap motors I'd like to try using a rear diff from something like a Sierra or Freelander and mount a motor directly above it, with belt drive to the diff input. I've checked the design specs for the Gates Carbon belts, and with a 36mm wide belt you can easily put 100 kW + into the diff.
 
#15 ·
I hadn't realised the Berlingo motor incorporated the diff and CV joints. That's very interesting, just a shame it's Sepex as it means a very limited choice of controllers. Do you happen to know what diameter the motor is Woody? Eight inches would be about the maximum you could get into a Mini without setting the drive shafts at an angle.
 
#17 ·
I can't remember what the diameter was, but the motor is a square section with the corners knocked off. Maybe about 10"?

This is what one looks like.



You might get an idea of scale here.


The controller.
 
#16 ·
I did a quick search on the Battery Vehicle Society forum and came up with this. Maybe worth a try to see if they still have some.

I saw someone was breaking an electrique on ebay and called to see if the had the vaccum pump and controller for sale, to be told they had SIX electriques and they'd put me through to the owner as he was working out what to do with them!

I spoke very briefly to the owner who put me on hold/lost me a few times and appeared very stressed about anyone coming down to see the vehicle(s) for a week or so - looks like he's been fielding quite a few calls about them...

Here's the ebay link to the "elctrique motor/gearbox for sale".

http://cgi.ebay.co.uk/Citroen-Berlingo- ... 4a9dec09db


quote
" We are selling the pictured electric engine and gearbox from a 2000 Citroen Berlingo Electrique E500

Sold as seen

We would prefer the lucky winner to pickup in person, but can get it delivered at your cost
(contact us for pricing BEFORE bidding if you cannot collect in person)

We will try to answer your emails, but for a faster response please ring us

VAT included in the price.

Viewing before auctions end is recommended, contact us to arrange

We are open
Monday - Friday 9am till 5pm
Saturday 9am till 4pm

Car Components Gosport Ltd
(02392) 501511"


/quote

I've left my number as I'm after a couple of brake servo pumps/controllers, and possibly a new motor controller - I guess I'm not the only one in a queue for one!

Tim
http://www.batteryvehiclesociety.org.uk/bvsorguk/forums/viewtopic.php?f=6&t=2417&hilit=gosport


Not sure if the link will work if you are not signed in.
 
#19 ·
Hi Studebaker

I was sorely tempted to do a mini - I used to have a mini with a Lancia twin cam in the front

My tuppence worth
A mini is light - a 9 inch or 11 inch DC motor with a decent controller and a 3 : 1 diff should be able to spin tires
This means a gearbox is unnecessary

I would be thinking about something like a Subaru or Sierra diff in the middle at the front
I would put the motor in the boot with a drive-shaft along the exhaust tunnel
- would probably need to cut the tunnel out and weld in a bigger one

You could reverse this for rear wheel drive - but then its not a mini
 
#20 ·
Yes, but then you would have to turn the diff around. I think they deigned to spin in certain direction. You know the annoying whizz that comes from diff when you reversing. You’d have it all the time in the set up where diff is spinning in opposite direction.
 
#21 ·
Hi Folks,

A friend of mine has a Kewet (possibly smaller than your mini), and she replaced the old worn-out DC motor with an AC motor from HPEVS. The motor is the AC50, and can be ordered from the factory with a transaxle. She was able to fit it in using Geo Metro drive shafts, with no machining needed.

Cheers,
Peter
 
#23 ·
Well, not quite all. Not sure what the deal is. However, they do have phone numbers (how 20th century!) on their website tho.

I'll see if I can locate an email address for you. Another possibility is for an EV vendor near you to order it...not sure who would be best for Ireland.

Cheers,
Peter
 
#27 ·
I was just reading through Caspar's build thread and noticed there's a slight problem with the Think system. Top speed for the Think was limited by the controller to 90 kph, but with 10" Mini wheels that drops to 70 kph.

Caspar, if you're following this, did you manage to find out how to increase the controller's rpm limit?
 
#31 ·
The HPEVS transaxle has a ratio of 8.5:1 - the transaxle is single-speed. The AC50 has a max motor speed of 8500. The limitation is actually the controller, as the motor and the transmission have a top end of 10K RPM.

She's able to get 65MPH out of her Kewet using this combination.

Cheers,
Peter
 
#34 ·
Thank you. I have a Swift (http://www.evalbum.com/3060) with an AC50 and nominal 115V pack. With 8.5:1 the estimated zero to 40 mph time would be about 7 sec and zero to 60 mph would be about 23 sec. It really dies at the end due to low torque at high rpm. The zero to 60 mph time with the original transmission is about 16 sec (measured). I don't need 5 speeds, so kind of watching for something like 2 speeds, and thought maybe 1, but the AC50 doesn't have enough power for that to work well at highway speeds. The 8.5:1 should work well and be very simple and convenient for lower speed city/secondary road driving though - all depends on what you want.
 
#33 ·





And it’s done.






What the hell was I thinking buying this car? Funny story BTW. I went to see two other minis. Arranged meetings with sellers, but they never showed up. Stopped to answer me calls when I told them I’m there and waiting. What the bloody hell these people are playing at I was asking myself. Are they listing their cars for sale out of boredom?

When I went to see the third one and the guy actually came, I felt like I hit a lotto jackpot. But when I seen the car I gasped in despair. What the hell I said to myself. Is now or never. Didn’t even tried to talk the price down. Bought it just to get it over with.

So, here we are…
 
#35 ·
You were thinking it's better to have something work on than to spend all day waiting for flakes that might not have anything better to offer.

I think that is a great size motor for this car. Any chance you will have enough space to mount it flat with a diff attached? If so, you will have a fair amount of space on top of it for other stuff.

The stock output shafts are pretty close to the cabin floor so it may be possible. If so, it's a very good option for mini conversions.
 
#36 ·
You think? Well, lets hope so, because motor is bought. I’m not sure about attaching it directly to the diff. Regular differentials have a ratio of about 4: 1, little less. I’d say it’s to low. This HPEVS transaxle Ptompson was mentioning could do for me. But where to buy it?
 
#37 ·
Hi Studebaker,

I sent you two private messages with info about the transaxle - I believe there is a company in the UK that sells them. You'll have to check out the info I sent and see if that works for you.

For those following, the transaxle is from Graziano, and is the UVT 900 gearbox. My friend had it modified to use 8.5:1 instead of the more standards 10.5:1.

Cheers, Peter
 
#38 ·
Hi guys.

Just waned to write few words so you wouldn’t think I gave up. Bet you thought I did. Not a chance. I’ll stick with you for a while. Well, it takes more than this





or this




to put me off.


Looks like I’m in for a long haul, but I won’t be boring you with progress of car restoration. Is not that forum. As far as conversion is concerned - the motor arrived yesterday. It is AC50.









I’ve pretty much made my mind up, that I’ll be hooking it up to this transaxle.



However, before I order it I need to get further with the car itself. To have something one can call a car, in the fist place. Now, as you well can see… I don’t.

Cheers
Chris
 
#39 ·
Glad to see you're still at it. I reckon that's just about the ideal choice of motor and transmission for the Mini. Does the transmission come with CV joints, or do you have to get those made up?

Looks like you're well set up to replace those rusty panels. I'm envious of your workspace. I have a tiny little British garage with not even enough space for a Mini, so I cheated and bought a plastic bodied replica :)
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top