sounds like a pretty well thought out plan. I assume you are getting the 144v kit.

with 100ah batteries your range will probably be about 80km/50 miles. If you want to get to 100+km go for the 160ah batteries, Other than that you are talking about using what I often recommend to people.

you won't get a significant weight reduction from going to manual steering, but the overall conversion will be simpler. there are 12V electric power steering pumps you could retrofit but you will need a much bigger DC/DC converter if you did that.

I went to manual steering on my scion xB conversion and it works fine.

good luck!

 

with 100ah batteries your range will probably be about 80km/50 miles. If you want to get to 100+km go for the 160ah batteries, Other than that you are talking about using what I often recommend to people.

I'm just a field Tech not an engineer. WHY would someone go to all of the expense and trouble to buy cells/batteries that only achieve 60 miles or less, with limited speed? I have been using Voltronix Prismatic 260 a/h cells (36 total) and can achieve 65 mph with 100 mile range. AND what's the deal with CALB cells? Just askin?

 

Hi MrZion
I gather you are converting one of those huge BMW things and not a "proper" Cooper S!

Anyway I would suggest a change of tack - How about getting a complete crashed Nissan Leaf and doing a complete transaxle swap

You will start with about twice the power that you can get from an AC-50 and you get all of the expensive bits in the "kit"

The later Leafs have the inverter mounted on top of the motor which may be a bit too high for your bonnet line - you could go for an earlier one or move the invertor

 

That would be a good idea if I had not already bought the mini and started stripping it down, but maybe as a future project that could be a sweet idea!

sounds like a pretty well thought out plan. I assume you are getting the 144v kit.

with 100ah batteries your range will probably be about 80km/50 miles. If you want to get to 100+km go for the 160ah batteries, Other than that you are talking about using what I often recommend to people.

you won't get a significant weight reduction from going to manual steering, but the overall conversion will be simpler. there are 12V electric power steering pumps you could retrofit but you will need a much bigger DC/DC converter if you did that.

I went to manual steering on my scion xB conversion and it works fine.

good luck!

Yes I was planning on using the 144V system, and at the very lowest 120V. I say 120V because these boys down in California, EV4U custom's, seem to have used 120 volt system, If my memory serves me correctly.

And yea my model put the required Ah's for my batteries right in the neighborhood of 160 Ah, which is good to hear someone else say that number!

I am positive of nothing, but I am reasonably certain that that year of Mini Cooper might come with an electric power steering pump.
Like this: https://www.ebay.com/itm/271911614942

But if not, I suppose it's no great loss.

Sorry I am not understanding why I would need an electric power steering pump if I convert to a manual steering system?

Yes the new BMW mini's do use electro hydraulic steering pumps so you shouldn't have to touch it. If I remember correctly the suffered from cooling issues so make sure the fan gets some good air flow.

So from the response by akseminole and you, it seems that I need a power steering pump even though I plan to convert this to a manual steering pump. If this is the case thanks for the heads up!

 

I wonder how easily a Nissan Leaf (uncrashed) could be taken apart and installed onto the Mini Cooper frame? Dealing with the transmission/driveshaft or the front wheel drive/rear wheel drive issue would be the worst of it. Mounting the battery pack would be tricky as well. Integrating the gauges would take some work.

But, I would probably use this method if I were starting over with my pick-up truck.

 

I am positive of nothing, but I am reasonably certain that that year of Mini Cooper might come with an electric power steering pump.
Like this: https://www.ebay.com/itm/271911614942

But if not, I suppose it's no great loss.

 

Yes the new BMW mini's do use electro hydraulic steering pumps so you shouldn't have to touch it. If I remember correctly the suffered from cooling issues so make sure the fan gets some good air flow.

 

Hi Mr Zion

I think you misunderstood
I'm suggesting that you keep your "mini" and put the transaxle from a Nissan Leaf in place of your current IC engine and gearbox

You buy a complete Leaf - and transfer all of the bits
You end up with a modern electric drive system batteries and charger in your mini

About twice the power of the AC-50 and probably a lot cheaper

 

I completely did misunderstand! that is a really interesting idea Duncan, I will for sure look into this!

Have you done this?

A word of caution: the Curtis 1239 controller puts out less current (500 A vs 650 A) than the 1238 controller, and this generates noticeably less torque. So I'd stay with the lower voltage design if I could.

Not sure why you'd bother with CALB cells these days, when you can buy packs out of a crashed Leaf or Volt for a fraction of their cost. Unlike the CALBs, these are OEM vehicle batteries and higher energy density. But you will need a BMS with them- I recommend a BMS any time Li-ion chemistry is used, as minimally necessary safety equipment.

Transplanting a Leaf into your car is a much more challenging project. Lots of people talk about it, and several are attempting, but I'm not aware of anyone who has done it yet. Duncan is right though- a crashed Leaf is a car conversion kit on wheels, with the parts costing only a fraction of what they'd cost if you bought them as conversion parts. There's at least one annoying thing in the way though- the vehicle control system. Your 2003 BMW Cooper has one too, and it will take some screwing around to deal with its unhappiness once you yank out the engine.

There are promising options to take these OEM transaxles and their inverters and lobotomize them so they can be operated without the vehicle's original vehicle control unit. That saves a lot of screwing around trying to calm the car back down after you've removed three-quarters of its sensors etc.

About your first paragraph, just to make sure I'm on the same page as you. Your saying since the controller produces less current, and a motors torque is proportional to the current, the 120V system would generate higher current than the 144V system? (Sorry if i'm way out)

I'll definetly look into buying packs out of those crashed leafs, not sure exactly where to start but that's the beauty of google!

Yea, I am really interested in what Duncan said about the transaxle swap. Just one craigslist search, and 30 seconds later I found a pretty new leaf for around 5k. Seem's most of them are automatics which I kind of find interesting, so I gotta search for a manual one if I end up heading down this road. Have you had experience toubleshooting the vehicle control system being unhappy once you swap out a motor?

If you absolutely must convert your Mini to a manual steering box for personal reasons, that is up to you.

I was simply pointing out that if your car in fact came with the electro hydraulic power steering pump already installed, that it would be a lot less work to simply retain power steering.
No need to find a manual steering box that fits, possibly fabricate mounts, etc.

It's possible that your Mini came with the standard power steering pump which is engine driven, in that case I see no reason not to go manual as you wish to do.

My comment was only applicable if, in fact, your car did come with the electric pump rather than the belt driven pump.

My point, if there is one, is that your car would be already set up with an OEM electro hydraulic power steering system which would be as easy to use as making sure that your fuses were in working order and that your DC/DC was capable of keeping your auxiliary battery charged.

As opposed to pulling it all out, and installing an entirely new steering setup in the car, possibly having to chase down gremlins in the system caused by error codes because the vehicles computer is wondering where it's power steering pump went.

It just seems like extra work on top of the task of replacing the drivetrain..

I'm not trying to dissuade you from doing what you want to do with your project, if this is truly what you want to do. Go for it.

Sorry didn't mean to come across as intense, but rather curious.

You make a good point, the one thing that I would be curious about is how much power savings do you get when you compare power to manual steering? The only reason I originally thought of manual steering is because I have read quite a bit of conversions doing this, so I just assumed the power savings must be worth it. But whether it is or isn't I am unsure. But as you pointed out if its already there, why make things difficult.

 

A word of caution: the Curtis 1239 controller puts out less current (500 A vs 650 A) than the 1238 controller, and this generates noticeably less torque. So I'd stay with the lower voltage design if I could.

Not sure why you'd bother with CALB cells these days, when you can buy packs out of a crashed Leaf or Volt for a fraction of their cost. Unlike the CALBs, these are OEM vehicle batteries and higher energy density. But you will need a BMS with them- I recommend a BMS any time Li-ion chemistry is used, as minimally necessary safety equipment.

Transplanting a Leaf into your car is a much more challenging project. Lots of people talk about it, and several are attempting, but I'm not aware of anyone who has done it yet. Duncan is right though- a crashed Leaf is a car conversion kit on wheels, with the parts costing only a fraction of what they'd cost if you bought them as conversion parts. There's at least one annoying thing in the way though- the vehicle control system. Your 2003 BMW Cooper has one too, and it will take some screwing around to deal with its unhappiness once you yank out the engine.

There are promising options to take these OEM transaxles and their inverters and lobotomize them so they can be operated without the vehicle's original vehicle control unit. That saves a lot of screwing around trying to calm the car back down after you've removed three-quarters of its sensors etc.

 

If you absolutely must convert your Mini to a manual steering box for personal reasons, that is up to you.

I was simply pointing out that if your car in fact came with the electro hydraulic power steering pump already installed, that it would be a lot less work to simply retain power steering.
No need to find a manual steering box that fits, possibly fabricate mounts, etc.

It's possible that your Mini came with the standard power steering pump which is engine driven, in that case I see no reason not to go manual as you wish to do.

My comment was only applicable if, in fact, your car did come with the electric pump rather than the belt driven pump.

My point, if there is one, is that your car would be already set up with an OEM electro hydraulic power steering system which would be as easy to use as making sure that your fuses were in working order and that your DC/DC was capable of keeping your auxiliary battery charged.

As opposed to pulling it all out, and installing an entirely new steering setup in the car, possibly having to chase down gremlins in the system caused by error codes because the vehicles computer is wondering where it's power steering pump went.

It just seems like extra work on top of the task of replacing the drivetrain..

I'm not trying to dissuade you from doing what you want to do with your project, if this is truly what you want to do. Go for it.

 

I think that the majority of conversions which were changed over to a manual steering box came with a belt driven power steering pump when it had the ICE.

Rather than running a belt off of their motor and needing to idle the motor for the power steering pump to work, they chose to run with manual steering instead.

I am not qualified to answer whether the power savings would net you any significant range increases.

From the little that I have read about electro hydraulic power steering pumps, the major current draw comes when you are going slow. Like parking, parking lot etc. places where having power steering is actually desirable. They tend to have reduced power steering assist when you are at cruising speed, because the OEM knows that it is less necessary when you are at speed.


As for the Nissan leaf, it is not that the Nissan Leaf has an automatic transmission. They, for all intents and purposes, do not have a transmission in the traditional sense. Their transaxle has only one gear ratio and there is no need to shift.
There is no such thing as a manual Nissan Leaf.
Their motor spins up to 10,000+ rpm and the one gear ratio is adequate to drive the car to its maximum speed.
If this is not adequate for your purposes, you could dismount the motor from its transaxle, but then you would need to figure out a way to mount it to your transaxle and that sounds like a hassle.

 

New Problem:

I have hit a weird roadblock, I have disassembled the exhaust system, intercooler, wheels, and other bits and pieces within the engine bay; but, when I took my impact wrenched to the left tie rod end it came off easy, and the the arm separated fine. The right side though, the nut came off fine, but it seems that the drive axle on this side is under tremendous pressure, and I can not disassembly the tie rod end. I asked someone, and they think it could be just rust, but I don't think it is because when I try and push the boot from side to side it doesn't budge at all.

Any thoughts?

 

If you have the room, put the nut back on with a gap between the nut and rod then whack the nut with either a 4lb sledge or air chisel after you warm it up with a torch a wee bit. Might need to replace the end afterwards. Support the tie rod before whacking so it has a fair amount of weight hanging on it.

 

I didn't end up heating anything up, i'm in quite a small garage so it would be a little nerve racking, but I did end up giving a good wack! I ended up for a couple of days spraying a mix of ATF and automatic trans oil where the outer tie rod was, then getting a wheel puller as in the picture and putting in between the nut and housing of the hub, just tightened until it just popped right out! thanks for the suggestion though!

 

Last night I had a good run at getting some stuff separated. Funny enough which took me the longest to get out last night was the ECU, there are two multi-pin male plug-in clips that insert into the ECU, and to get those off there were these well hidden tabs that you have to fully pull out, before you can unplug the the male plug in's.

As you can see from the different engine pictures, I took off the compressor and the alternator, by first removing the belt and then swinging the compressor off to the side so I can get further at the engine.

I've nearly got everything off the top of the engine, still some whose's and wiring to label to make sure I have a clue on whats what. Where I am at is taking the axles out, but where the outer ball joint meets the hub there is some serious contact rust happening, so I'm using my awesome concoction and spraying right in that joint, then hopefully a pickle fork will be able to vibrate this joint loose so I can finally remove the axle. These axles are quite the task!

 

Nice work, keep the updates coming!

I enjoyed this part of the process a lot.

Regarding the tie-rod, they are normally a press fit/ very firm fit so you normally need to whack them with a hammer or use some sort of puller or wedge to get them out.

Soaking stuff does wonders, heat and whacking things with a hammer/ using an impact driver are a good next step. good luck.

 

Totally! I am doing this project with my father, and he got a pretty good photo that I thought summed up one of the things you said!

 

The latest news:

Got the engine out last night!! the hardest part was battling the outter ball joints on both sides of the car, the way we got around the issue is zip cutting through the boot/bolt. Was it ever a relief to get those off! After that it was all gravy from there, just figuring out what to unplug and out she came some time later.

Before starting this project, I really researched the living day lights out of every possible aspect of this project, but at the end of the day it was just research and it was easy to say that I was going to do this project. Now that I am actually close'ish to needing parts and such, it is a crazy and exciting feeling!

Like I said in my original post, if people could look at my circuit diagram I have posted and give me feedback that would be fantastic. I was supposed to digitize/update it, but I have not had the time in the past while. Soon to come.

Here are some more photo's:

 

The leaf batteries can be found in a salvage yard, just search on car-part.com . I got a pack for about $3,500 from a yard in Virginia delivered to my door in Florida for $150. I am going to wire them in 3p16s for 180 AH and 120V. I think the equivalent in CALB batteries would be about 3 times as much money. So instead of trying to use the entire Leaf I think the batteries are the most useful part.

 

You are totally right about cost, and that's why I am so enticed about using as many components about the leaf, the bang for you buck is not achievable by buying components individually. Unless you go for used components, and do some serious digging around.

That is a good pack configuration though, thanks for the heads up!

 

Speaking as someone who drives a 2004 mini cooper daily, and has had the power steering fail while driving in a parking lot, you're definitely going to want power steering. It's not too bad when you're moving, but at low speeds, you have to be Hercules to turn that wheel even a little.

I'm considering an EV conversion on a classic car, and buying an EV mini when they eventually make them available, so I'm watching your thread with interest!

Cheers,
Duane

 

Have you driven other types of manual steering before??

I'm glad your keeping an eye on my thread, feel free to give input at any time!

 

Hello All,

Sorry it's been awhile since I posted last, I caught a nasty flu for a little bit there.

I was able to get this minty mini cooper for quite cheap because the owner didn't want to deal with the clutch, and since I pulled the engine out recently the next part of this project was to take out the clutch. I've never actually done a clutch before. But my god was there metal shards everywhere. ball bearings all over the place, the throw-out bearing was shredded, the outer clutch plate cover was absolutely mauled over. The flywheel itself was actually barely even scratched which was a good surprise. I mean, here the pictures speak more than a thousand words....

I'm at the point in this project where I need to choose a fork in the road. The fork being either I chose to go down the one road, which is buy a used leaf and strip it for parts, or buy the parts individually. The advantages of the leaf is you pay essentially half what you would pay, compared to individually buying the parts, and you get double the horsepower and battery capacity and other such things. The negative, from what I can tell is getting the system to interface with my mini, which sounds like it will be a tone of CAN interface issues and potentially ECU codes to deal with. The advantage of buying the components individually is that I get to actually implement my circuit design, and get a true design and implementation experience. the disadvantage is it costs way more, and I don't get nearly the battery capacity and horsepower a leaf gets at that price point.

I am really interested in what you guys have to say, so I would really appreciate your opinions. Keep in mind, I am trying to learn as much as I possibly can from this experience.

Cheers

 

Hello Everyone,

I have been a ghost on the forum for awhile, really it was just school for the last while has gotten me completely taken up. Now though over the next couple of months I plan on putting up a huge push and hopefully finishing this. I've been developing my circuit, my energy consumption model, as well as figuring out vendors for which components I'm going to buy from for the last while.

Something that I was quite shocked about was how much batteries are. This nearly put a stop to my project, but instead I have found multiple vendors (which all of them I have talked to) and I have decided that I will be going to get tesla modules, 24V at 120ah. I've done my research and talked to a whole bunch of peoples and experts and the consensus is I'll just have to be more conscious of my temperature and over/under voltage. But please do share advice, and what your thoughts are on monitoring and such.

Also, this is my most updated circuit image so please comment on it. You'll notice the colour coding is not really a thing yet, nor are some of the end connections coming out of the controller.

What fuse/wiring sizing do you guys recommend for the curtis 1239 controller and why?

Cheers

 

Hey,
Nice build, i cant comment on your circuit diagram, it looks like dutch to me.
Thinking over the question in your last post about buying OEM leaf/ volt or buying individual parts.
I understand your conundrum having asked that question myself. I think the extra range and value pays for the difficulty of interfacing issues. thats my vote. plenty of cheapish aftermarket guages and bits or you could massage the leaf bits to fit in your car

Glenn

 

I understand your conundrum having asked that question myself. I think the extra range and value pays for the difficulty of interfacing issues. thats my vote. plenty of cheapish aftermarket guages and bits or you could massage the leaf bits to fit in your car

Glenn

Funnily enough I actually decided against doing the Leaf, the reasons are the following:

1) I talked to a leaf mechanic at a shop, and we got going about the CAN signals in which I didn't have any of the hardware/software to monitor/program the signals with, as well as he said if the signals are out of phase at all the system will throw more errors than you can imagine.

2) I looked and looked and couldn't find anyone who has actually made a functioning vehicle using the leaf drive system, I'm not saying that because I haven't found it so therefore it doesn't exist, but rather I just found that nerve racking.

3) You will have to learn how the CAN system works, and you will most likely have to reverse engineer their CAN signals.

With all this in mind I am going to buy individual parts, hopefully it works out!

 

Hey guys,

I'll make this a long post to summarise what's been going on the past couple of months.

I have been MIA from posting anything, but not necessarily from the project. I have been spec'ing out the components I am going to use in my conversion for the last while, and bugging/asking as many people as possible to get the info I needed to make these decisions. (Sorry to those people)

Also, I moved back to where I have garage access! This has given me much more space, many more tools, and a industrial size pneumatic tank!

What I have decided use:

1) I am using Tesla Model S batteries out of a P85 pack. Very excited about this, I am stringing 5 modules in series to give nominally 120V @ ~243Ah

2) Using an AC-50/Curtis 1238 Controller set up at 108 Volts

3) Using CanEV to supply my parts, which Randy has been a huge help! I would recommend them to anyone.

4) At this moment I believe I'll be using ZEVA BMS system paired with an Elcon PFC 2500 charger. Ian at ZEVA has been an incredible help. For anyone looking into what BMS to use give ZEVA a look, Ian gets two thumbs up!

As I said before for the last while I have been spec'ing parts out, but also setting up my works space as well as continuing to strip parts off of the mini.

Recently I took out the fuel tank, which was more work than I thought it was going to be as the e-brake cables straddled the under carriage of the fuel tank. So I had to go and disassemble the e-brake cables starting from the centre console, and then making my way back to the rear brakes.

I have started to to think about my battery box design/layout, and with the space given I am going to have to split my pack up into two separate packs. One in the trunk and the other where the fuel tank used to be. I'm still working on the cooling system, but talking to Wayne Bickley has given me a very good idea on how to implement this system.

For creating the vacuum for the power assist brakes, in the name of being budget friendly I am going to create the reservoir out of PVC, and install it in cavity underneath the vehicle that runs from front to the back. Then using a diaphragm (louder) pump, vacuum switch, and a relay I'll hook this all up back to the brake booster to give the vacuum it needs.

Edit:
Just received my first Tesla Model S Battery Module, and wow is it ever amazing the first time you see one!

 

Following VERY closely - I`m about to do the same on my 2002 Cooper and I feel this thread my end up being gold in the future. Would you mind PMming me your email?

 

Hello Guys,

In my previous post I uploaded a picture of my tesla model s battery, and a picture of the pcb. I noticed on the pcb, when comparing it to other pictures I have found online of tesla model s pcb's, that the voltage tap through holes on the right are scattered for me (not in a straight line like most other peoples), and mine does not say model s with a car drawn.

Does anyone know why?

 

Just ordered my Tesla batteries as well! Looking forward to seeing how you wire up the ZEVA BMS system as that's primarily what I'm looking at.

 

I'm interested in this as well. I did a Honda Del Sol a few years ago and am getting the itch to do another. A mini seems like a good candidate. Thanks for the updates!

 

Where do you guys get the tesla batteries and how much are they? I paid ~$7k for a CALB 20kwh pack about 5 years and was hoping to pay a lot less now. But from what have been able to find, a Tesla pack of equivalent size would be roughly the same cost.

 

About your previous comment, there two things to consider with a mini, the weight and amount of area you have to play with. The weight for a car this size is quite high, and the area you have is limited. So just keep that in mind, other than that if you've thought about that than its been tons of fun!

Where did you pay for 7k a 20 kwh pack? What makes the tesla batteries far superior is the engineering that goes into the modules themselves, and the energy density. Each chemistry has there pro's and cons, but these are a couple of big pro's for the tesla modules. Also the amount of space that my 29 kwh pack, 5 modules, will take up will be a lot less than what the calbs would take up.