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Discussion Starter #1
Hi everyone,
I am restoring a 1996 Mini with the intention to convert to electric.
I've been following some of the threads and have been planning on using a Nissan Leaf.
However I really want a range of 100 miles and am struggling to work out how to fit enough batteries in such a small car without losing the rear seats.
I have seen the Swind e mini has managed it but I don't have 80 grand to put into it
Has anyone considered an iMiev, Zoe or anything else that might be more suitable than a Leaf?
Tia


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As far as I see here, the Leaf-motor is quite large, however it can fit into the Mini; seems to be a hard task.
I still believe that the TH!NK-drivetrain fits the best. The whole unit incl. 45kg batteries (18650 cells), good for 50km, are in the engine compartment of my current conversion, you can hide another battery-pack UNDER the rear seats (if you slightly modify the sheet below), and another pack fits comfortably in the trunk if you expand the original MINI battery tray to the very left side. And with little modification another pack can be hidden under the front seats. The MINI offers enough space for batteries to meet your specifications.
Nice to read about another classic MINI coming back to the road with a reasonable engine.
Good Success!
Markus
 

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Discussion Starter #5
As far as I see here, the Leaf-motor is quite large, however it can fit into the Mini; seems to be a hard task.
I still believe that the TH!NK-drivetrain fits the best. The whole unit incl. 45kg batteries (18650 cells), good for 50km, are in the engine compartment of my current conversion, you can hide another battery-pack UNDER the rear seats (if you slightly modify the sheet below), and another pack fits comfortably in the trunk if you expand the original MINI battery tray to the very left side. And with little modification another pack can be hidden under the front seats. The MINI offers enough space for batteries to meet your specifications.
Nice to read about another classic MINI coming back to the road with a reasonable engine.
Good Success!
Markus
Thanks Markus
Do you have a thread for your build?
Cheers
Scott

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There is somewhat:



I am not a typical "blogger" (probably the wrong generation), so please don't be too disappointed: other people write more and place more and better pictures. Of course, if you need any information, I will be happy to share with you people.

Markus
 

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Discussion Starter #8
There is somewhat:



I am not a typical "blogger" (probably the wrong generation), so please don't be too disappointed: other people write more and place more and better pictures. Of course, if you need any information, I will be happy to share with you people.

Markus
Thanks Markus
I'll have a look

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Im using the mitshubishi oultander rear motor, ive already got it fitted into the mini subframe. Ive got a slightly different issue with battery location as im doing it in a mini marcos.
The issue i have with the Swind-E conversion is that they cut into the front bulkhead and the floors of the car which isnt great and opens it up to IVA fun and games.
 

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Hi everyone,
I am restoring a 1996 Mini with the intention to convert to electric.
I've been following some of the threads and have been planning on using a Nissan Leaf.
However I really want a range of 100 miles and am struggling to work out how to fit enough batteries in such a small car without losing the rear seats.
I have seen the Swind e mini has managed it but I don't have 80 grand to put into it
Has anyone considered an iMiev, Zoe or anything else that might be more suitable than a Leaf?
Tia


Sent from my moto g(8) power lite using Tapatalk
The Leaf drive train is actually quite compact once the bulky liquid cooled charger and dc converter are removed.
Using our VCU : VCU for UQM Motor It is ideal for front wheel drive or rear wheel drive applications using the Leaf differential. Cutting the half shafts and mating to the donor car is much easier, (and cheaper), than making a custom adapter to a manual transmission. We have placed this drive into a Geo Metro, a
Mazda Miata, and are now working on a Toyota Tacoma conversion. great for early VW's. High torque, powerful, and automotive grade reliability. We offer much more compact chargers, dc converters, and bms that can be mounted where space allows.
 

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If you want to keep the rear seat and get 100mi, I'd try and stick the motor in the rear. You'll have to build your own mounts, and use Miata hubs and brakes, but it'd be a wicked car when you're done. You could easily fit half a Leaf pack under the hood, and the other half under the seats and in the trunk above the motor. It's more or less what you want the weight balance to be (and in a RWD car, I'd aim for 47% front, 53% rear). There's room for a few modules between the front seats, in front of the handbrake as well.

It's not so much the motor that's your issue, it's the batteries. The Leaf modules aren't the most dense, but they're a great form factor for squeezing into nooks and crannies. At low average speeds in warm temps, I'm getting 60-80mi out of a mere 30 Leaf modules (15kW) in my Mini.
 

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Discussion Starter #12
If you want to keep the rear seat and get 100mi, I'd try and stick the motor in the rear. You'll have to build your own mounts, and use Miata hubs and brakes, but it'd be a wicked car when you're done. You could easily fit half a Leaf pack under the hood, and the other half under the seats and in the trunk above the motor. It's more or less what you want the weight balance to be (and in a RWD car, I'd aim for 47% front, 53% rear). There's room for a few modules between the front seats, in front of the handbrake as well.

It's not so much the motor that's your issue, it's the batteries. The Leaf modules aren't the most dense, but they're a great form factor for squeezing into nooks and crannies. At low average speeds in warm temps, I'm getting 60-80mi out of a mere 30 Leaf modules (15kW) in my Mini.
You're not the first to suggest RWD, it would be an extra challenge but could be awesome.

I'm currently looking at all the different battery modules to see if a Zoe or i3 pack would be easier to mount in the mini.
Trying to find the info and be confident that the info is correct is tricky.
I think the Zoe modules are 373x204x140mm and the i3 are 150x310x410.
I'm going to have to make a concrete decision soon as I'm repairing the shell now ( you can follow on my YouTube channel Mini Life Crisis).

Really interesting to hear you're getting that sort of mileage on a charge, I generally get about the same out of my i3 which takes just under 18kwh to charge.

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RWD would be good for a further reason: wheels will not spin that easily as they do on a FWD. I am considering a 4WD with my project #3 Mini.
Any suggestions which rear axle to use?
Markus
 

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The trick bit seems to be getting Miata hubs/brakes onto the Mini rear subframe. Basically this, but without the full cage:


If you're really going AWD, you're looking at two Leaf motors, or using something like a RAV gearbox and differential, with a VTEC subframe up front and this in the rear:


It gets pricey fast. I wish they just sold this, but with drivable hubs:


It's worth noting that, after going from old/cracked tires to a set of Yokohama A032Rs on my car, front wheel spin has been greatly reduced. I still like the idea of RWD, but FWD is working well and fits the chassis/suspension design...To pay the cost of going AWD, I think you'd really want a specific reason for it.
 

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the beam axle that tremelune has linked to has been around for many years, i fitted one to a mini clubman and it made the rear end skittish, hence why none of the racing minis in competition use them.

RWD would be great and its what the guys in the UK are doing with the R300 which is a funny name as thats what early racing caterhams are named but i think it has something to do with power to weight ratio.

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I looked at the LG Chem batteries and had a quote from Electric Classic Cars for them but the cost is still a lot higher than buying a second hand battery pack. Im now looking at outlander / vw and BMW hybrid battery packs. Range isnt so much of a priority as i want to use the marcos on the track so as long as it lasts a couple of track sessions at my local track thats all i need.
 

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I looked at the LG Chem batteries and had a quote from Electric Classic Cars for them but the cost is still a lot higher than buying a second hand battery pack. Im now looking at outlander / vw and BMW hybrid battery packs.
If you're looking at second-hand, the Chrysler Pacifica Hybrid pack is a set of six of those commonly offered LG Chem 16S (~60V) modules. The Outlander PHEV pack is, unusually for current production vehicles, only 80S (~300 V nominal); that may be fine.
 

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the beam axle that tremelune has linked to has been around for many years, i fitted one to a mini clubman and it made the rear end skittish, hence why none of the racing minis in competition use them.
Beam axle? Maybe you're referring to an earlier post, but in today's post the suspensions in the mid-engine kit and in the rear coil-over subframe are independent by trailing arms, and the all-wheel-drive rear subframe has upper and lower A-arms (the Mazda Miata NA/NB design - not quite double wishbone). All three are different (the two trailing arm systems are differently constructed, but of the same type) and none are beam axles. The rear coil-over subframe incorporates an anti-sway bar - if that is too stiff it would make the rear end "skittish", but it could be replaced with a softer (smaller-diameter) bar, or simply omitted.
 

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RWD would be good for a further reason: wheels will not spin that easily as they do on a FWD. I am considering a 4WD with my project #3 Mini.
Any suggestions which rear axle to use?
The trick bit seems to be getting Miata hubs/brakes onto the Mini rear subframe..
In any small RWD project, Miata bits are good candidates... but they don't have the same wheel bolt pattern as a Mini: Mini is 4-on-4" (101.6 mm), early Miata is 4-on-100 mm. Close is not good enough in bolt pattern PCD (pitch circle diameter).

The wheel mismatch might not matter - a RWD Mini could end up rear-heavy (depending on battery location), and wider wheels might be used in the back, meaning that front and rear wheels wouldn't interchange anyway. As long as you can buy the same style of wheel for both ends, it would be a non-issue.

If you're really going AWD, you're looking at two Leaf motors, or using something like a RAV gearbox and differential, with a VTEC subframe up front and this in the rear:

{all wheel drive rear subframe}

It gets pricey fast.
Even for RWD (not AWD), this AWD subframe kit might be the way to go. It uses the NA/NB Miata/MX-5 rear suspension design, but with custom control arms, presumably to fit the much narrower track width of the Mini. It's easier to understand in context with this image of a completed installation (toward the front of the car is the top of the image).

I'm surprised that there is so much room under the trunk floor of the Mini to fit this relatively tall suspension - with no installation instructions, I don't know if this requires cutting out the floor above it. In many FWD cars the fuel tank, spare tire, or muffler would sit there... is it just the muffler in a Mini, or maybe the muffler below the floor with the spare and perhaps battery to top? I know the fuel tank is not there in a Mini.

With all that room - enough for a final drive unit (differential assembly) - it would be nice to be able to place the motor and gearbox there, but that's asking a lot and seems unlikely. This AWD kit uses the stock exhaust tunnel for the propeller shaft; it would be possible to mount a motor longitudinal under the rear seat, but the tunnel would need to be enlarged and it would be much higher than the seat base... and where does all of the battery go if the motor and final drive + suspension are taking all this space in the rear seat and trunk areas?

It would be unfortunate to build a RWD Mini for better drive traction with the rear weight bias, then end up piling the front so full of battery that the car is still front-heavy. It would be the reverse of the current silliness of production EVs based on FWD platforms, which drive the front wheels but are rear-heavy due to their centred to rear-biased underfloor battery packs. Of course, RWD with even a slight front weight bias is better than the reverse, and adding passengers and cargo shifts the weight distribution rearward.

I wish they just sold this, but with drivable hubs:

{rear coil-over subframe kit}
Ready-made would be nice, but that's certainly something that can be custom-fabricated by many shops and home builders. It has an interesting feature which mounts the hub carriers with two bolts, one of which can be adjusted to control toe; the same thing could be done with an adjustment at the inboard mount of the trailing arm instead, if you don't want to accommodate their anti-sway bar system.

A common production rear suspension design for FWD cars is to combine the trailing arms into one assembly with a beam joining them at the pivot axis. The middle part of the beam has to be able to twist to accommodate the arms moving different amounts, and acts as an anti-bar. In this design toe is not normally adjustable, as it stays fixed in the as-built condition unless the assembly gets damaged. This is simple to mount (just two forward mounting pivots plus springs and shocks for the whole thing), but not trivial to design because the deliberate twisting must be accommodated.

Early Miata (NA/NB) rear hubs are hard to use with anything other than the stock hub carriers (uprights), because the bearings mount directly into the hub carrier. Modern (so, newer than an NA or NB Miata/MX-5) practice is to use a replaceable hub and bearing assembly that bolts (with four bolts) into the upright - using those makes building a suspension arm easier, as it just needs a plate with the four bolt holes in the right pattern and a big hole for the hub - even U-Haul trailers have used this approach. You need this from something driven, which can be the rear of a RWD, the rear of an AWD, or even the front of a FWD (although these assemblies are more commonly used in the rear). The current (ND) Miata/MX-5 is an example. Of course, none of them will have a 4-on-4" wheel bolt pattern.
 

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I wonder if you could do something with the i3 rear subframe?
I don't think that the BMW i3 has a rear subframe - it appears to have an aluminum full frame, with a carbon-fibre body sitting on top. You could cut the rear section off of an i3 frame, complete with suspension and drive unit, but it is far too wide for a Mini.
 
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