Got my donor car! MR2 mk2 G Limited

[Night Train]

I am writing the project progress reports on diyelectriccar.com here mainly because there has been so much more activity there while I was planning the project.

Here's some more photos of the car and a video of the engine condition.

[timpootle]

So, is there anyone in the Salford/Manchester area who knows about MR2s who want to help out on the difficult stuff like removing the engine?

Apparently it isn't an easy job without a car lift! :(

Ooh, shiny :-)

No MR2 experience, but how hard can it be? I'll help with the big lift when you need it.

Battery purchase should be the last thing you do (he says, with a garage full of lithium that's been there for 10 months). Be careful of the C rating when choosing your LiFePO4 cells- my 200Ah cells will only supply 60A continuous, so I need 2 or 3 in parallel to feed the Berlingo at 162v. High voltages obviously draw less current for a given power, so you'll be OK if you choose an AC setup.

[Night Train]

Thanks Tim, I may take you up on the help.

Apparently the conventional method as recommended and approved by the MR2 owners club is complex requiring all the rear suspension out, the sub frame out and the engine dropped on the ground before the car is lifted 30" in the air and the engine dragged out. Refitting is a reversal of the process.

Another MR2 EV converter says it is possible to get it out the top if the exhaust manifold is cut off first.

I still have to get the rest of the ancilleries off and then I will start hacking at the exhaust and inlet manifolds before I pull the drive shafts.
Then I will build a gantry for the hoist.

But first it has to stop raining!




I have also found some possible motors at a fork lift motor rewinders.

This one is 11" x 15" but has a female splined shaft. It also has slots to vary the brush advance. It has been reconditioned but the client never returned for it. Series winding 65v 10.5kw. This looks good except for the female shaft. Possible with a bit of shaft machining.



This one is in bits and needs fair bit of work. It should be 48v series winding with 4 terminals. It has a male splined shaft. 9"x16". Will probably not bother with this one.



This one is 4 terminal series motor, 45v 4.5hp 2200rpm with a male splined shaft and a drive flange. 9"x 16" It mounts on two brackets on the sides of the case. It was from a milk float.



This one is another possible favorite. 11"x16" with a male shaft and drive flange. It also mounts on two brackets on the case sides like the milk float one above. 65v 6.5hp 2150 rpm


OK, so what are your opinions?
The chap wants approximately £400 serviced and sorted or £200 running on 12v but no repairs and servicing.

[ChrisB]

WOW I forgot how big forklift/float motors where

£400 seems a bit pricey for a huge hunk of a motor like that, have you thought about one of cedrics pancake jobbies, yeah it will cost a few bob more but size and weight wise they are incredible.

I had two 10kw 60v lynch motors in my fiesta and I could hold the pair (in their frame) with one hand, sort of gives you an idea of the weight difference

ChrisB

[Night Train]

So is that a 'no' then?

The big one in the first set of photos withthe female splines would be about £400, the other big one would be about £200 but I would have to take a chance on what it needed doing.

What are Lynch motors like for power, speed and cost as a comparison?

[Jeremy]

The big difference with a Lynch type motor will be efficiency, being a PM type motor Lynch motors tend to run at 85% or better. This equates to greater range and less heat, not to mention the very much lighter weight.

Worth saving up for, in my view.

Looks like an interesting project, BTW, I look forward to seeing how it turns out.

Jeremy

[GregsGarage]

I used a 95 series lynch motor in my Fiat 126 conversion, The car could do 55mph, but it only weighed 680kg. You would need 2 at least for the MR2, maybe more depending on what performance you are looking for and they are not cheap. Have a look on the Agni website, there is a simple formula to calculate how many motors you would need based on the weight and speed of the vehicle. Many conversions are done using forklift motors, but you have to be careful because you will probably exceed the name plate ratings, mainly on voltage. Many motors can run at higher voltages, but as you increase the voltage you increase the motors rpm. Max rpm is usually determined by the bearings and armature.

[ChrisB]

My twin 60v 10kw lynch's would get my Fiesta to 75mph and it was only really due to the motors max'ing out rev wise which stopped it going faster.

Would smoke the tyres in 1st and 2nd gear and could be provoked even in 3rd its was stunning.

You can see the pair of them in dumbell fashion in the below pic.



They are the two chrome looking disks near the top of the pic, yep thats 20kw, and they really are that small.


ChrisB

[Night Train]

Well the original intention was to get a forklift motor and over volt it to around 144-160 volts and advance the brush timing. This is on the basis that the motor would be relatively cheap and easy to use and the technology is fairly proven if archaic.

Now to make me consider the Agni or Lynch motor option I would need to know what price range I am looking at as I simply don't have a budget for this at all and I am working on whatever I can afford at the time and then save up for the LiFePO4s.

However, like the LiFePO4s I will find the money if I can justify it, the snazzy website isn't doing it for me and a Europe and USA dealer with a hotmail address doesn't inspire confidence either.



So convince me.

The MR2 has a max weight of 1250kg and no doubt I will reach that, and maybe some more, with the batteries.

I need to have a working range of 60-70 miles a day and I need to do 60+mph for 2/3 of the journey and 40-50mph for most of the remaining 1/3.

I am planning on 45 x 180Ah cells to give 144V and that should give me 71 mile range at 60mph on level ground in still air.
That is 293Wh/mile and 17.57kW required power.

If I had the cells in parallel to halve the voltage then I would be looking at about 73 volts and 240 Amps.

This would suggest that Chris' twin 60v 10kW set up would just about do it. So could I possibly be looking at a near identical motor controller set up?
If so, could you tell me how much that cost please and where I would be getting them from? Do I just send an email to a hotmail address? Is it that simple?

Also from Chris' photo the motors are coaxial to the gearbox. How have you connected it and have you got a clutch or a direct connection?

Sorry for all the questions but this has thrown a whole load of other factors into the equation that I need to take into account now. I only want to do this once and I can't really afford to make a test bed and then improve later. I also can't afford to make a very expensive car either with too much costly new technology so it is all a balance.

Thank you.

[GregsGarage]

Do I just send an email to a hotmail address? Is it that simple?

Yes.

Compared to the £400 forklift motor I think 2 Agni motors will be between 3-4x the cost. Another advantage to the Agni motor is you can easily have regenerative braking with the proper controller.

If I had the cells in parallel to halve the voltage then I would be looking at about 73 volts and 240 Amps.

Battery pack size sounds reasonable for what you want to achieve. A 46 cell pack connected 2P23S would be around 73 volts and 360ah