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Discussion Starter · #1 ·
I have decided to share some of my project so far. I am removing the FA20 from my 1st gen Subaru BRZ and putting in an EM57 from a 1st gen Nissan leaf. The project has had a slow start so far. It has been sitting for some time while I finished up with other work. I've noticed there are few projects regarding newer vehicles, especially those with extensive CAN networks and OBD; I suppose people prefer older vehicles for their projects.

With all the increased attention around electric vehicles lately, where did the electric sports car go? With the departure of the Tesla Roadster, I would argue there hasn't been any realistically priced car in that category since. It wasn't remotely affordable for the average person but was still significantly cheaper than others like the R8 e-tron and SLS electric. This leads me to building my own using the Subaru BRZ as a base vehicle.

123416


Project goals:
  • Retain all stock features
  • J1772 and DC fast charge
  • Meet or exceed stock performance
  • Minimum 90 miles range
Other planned project features:
  • Custom electric powertrain user interface/display
  • Composite aero panels
  • OBD functionality
  • Robust safety features
  • Electric A/C
Parts decided on include the EM57 motor and Chevrolet Volt batteries.

I would also like to share some info with the community if/when I get it. Since nobody will share the EM57 spline dimensions from what I can find, I will share that when I get it. I would also like to share how to operate the Volt BMS off-car if I am able to reverse engineer it.

In my next posts I will go over what has been done in preparation for engine removal and my design process. I am also considering making a companion video series if people are interested.
 

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Are you planning on keeping the transmission or ditching it? Good reasons for both but the BRZ has a ton of aftermarket support including high-ratio final drive gears so possibly direct driving from the EM57 to a 5.28:1 or higher diff would give you excellent performance and good top speed too.

I think a BRZ is a great candidate as long as you can find room for batteries!

+1 for Resolve-EV I also have one and very impressed so far.
 

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also height for the Power module stack. unless you split them, which is doable. but if you split them then it's less reasonable because the Charger and DCDC are huge for what they do.
 

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Discussion Starter · #6 ·
Spline diameters available here: Which friction disk to match Leaf splines - openinverter forum

If you go EM57 route, I heavily recommend the Resolve-EV Controller!
I took a look through this thread and it seems similar to other threads I have read here, which would be repurposing a friction disk. I was hoping to find the JIS spline spec to model my own part. Regardless, that is one of the first things I will have to figure out.

As for the controller, it would have been nice to know about your solution back before I bought my parts. I do have the Leaf charger module but I believe it is the 3.3KWh which doesn't have DC charging. I got it as with the motor but I was going to use my own charger and DC-DC. For now I have a thunderstruck VCU which I probably won't be using since it will be difficult to integrate with my intermediary computer and the rest of the car.

I will be using the manual transmission coupled with the EM57/inverter stack. A direct drive setup would be lighter and likely more efficient but I don't think it would be as enjoyable. From what it looks like there would be enough room to put the motor at least partially in the transmission tunnel since Subaru made it so large/mounted the engine far forward (a transaxle could be possible too). It's impossible to say how I will like it until the build is complete. A higher final drive ratio could help and there is also the possibility of removing gears or going to a different gear set.
 

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Discussion Starter · #7 ·
So far I have collected a substantial amount of CAN logs for every scenario I could think of. This would be anything from locking the doors to VSC activation. The BRZ is a simple vehicle electrically, so it has been relatively easy to figure out what is going on the bus.

A problem I expected to run was with the immobilizer system. I expected this to communicate with the ECU to fetch key RFIDs. However I disconnected the ECU and the immobilizer light still functions as it should. I will have to diff the logs to be sure. However I don't think any key data is stored in the ECU from what I saw with the ECU replacement process.

With the ECU disconnected I thought it would be a good time to try out some of the functions I've isolated, like activating EPS. Everything has worked well so far. Even running a log of the car driving back to the ECU showed great results. The speedometer and traction systems were a little confused since real wheel speed was 0 but all systems responded except for the oil and alternator lights. I believe these are mechanically activated and not run through the bus but I will have to investigate.

The engine will be out once the refrigerant is captured
 

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Discussion Starter · #8 · (Edited)
Engine is out. It was a fairly simple removal despite the lack of information online. Disconnect the harness, fuel lines, 2 ground straps, engine mounts and transmission bolts. The engine was being lifted out the third hour in but the headers were colliding with the fan shield. I finally gave in and removed the headers after trying every other solution. It was pretty easy since the studs had no rust; they looked like some special material.

Unfortunately the 12v battery had been leaking substantially and got battery acid all over the right side on the engine bay, pulling the paint off of the subframe. So before any other work can be done there will have to be some clean up and painting.

As a mock up I put my DC-DC and charger where the 12v battery used to be. They fit very well and I can use the existing mounts to fasten the two down. A more compact all in one unit would be better but this will work for now. The stock 12v will be recycled and will be substituted with a sealed motorcycle battery. Depending on the space remaining it may be able to occupy some of its old space but it will likely be relocated somewhere else.

Next I will be working on the transmission adapter and a block off plate for the starter motor hole.
 

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I have decided to share some of my project so far. I am removing the FA20 from my 1st gen Subaru BRZ and putting in an EM57 from a 1st gen Nissan leaf. The project has had a slow start so far. It has been sitting for some time while I finished up with other work. I've noticed there are few projects regarding newer vehicles, especially those with extensive CAN networks and OBD; I suppose people prefer older vehicles for their projects.

With all the increased attention around electric vehicles lately, where did the electric sports car go? With the departure of the Tesla Roadster, I would argue there hasn't been any realistically priced car in that category since. It wasn't remotely affordable for the average person but was still significantly cheaper than others like the R8 e-tron and SLS electric. This leads me to building my own using the Subaru BRZ as a base vehicle.

View attachment 123416

Project goals:
  • Retain all stock features
  • J1772 and DC fast charge
  • Meet or exceed stock performance
  • Minimum 90 miles range
Other planned project features:
  • Custom electric powertrain user interface/display
  • Composite aero panels
  • OBD functionality
  • Robust safety features
  • Electric A/C
Parts decided on include the EM57 motor and Chevrolet Volt batteries.

I would also like to share some info with the community if/when I get it. Since nobody will share the EM57 spline dimensions from what I can find, I will share that when I get it. I would also like to share how to operate the Volt BMS off-car if I am able to reverse engineer it.

In my next posts I will go over what has been done in preparation for engine removal and my design process. I am also considering making a companion video series if people are interested.
This exact build has been done well documented here: Toyota GT86 with Nissan Leaf Motor - openinverter forum

Em57 adapter plate cad files: GitHub - angusjo/adapter-plate
also I have couplers available for the leaf motors
Wire EDM machined out of 4140 chromoly
260$
123479
123480
 

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There’s this project, whom mounted a leaf motor in the rear of a legacy subframe Log into Facebook
123510

And in this case, I am in the early stages of designing and testing some stub shafts for the leaf gearbox, which will have 25 Subaru outer splines. so suby axles will just mate to a leaf gear box!
Rim Bicycle part Auto part Circle Font


The reasoning behind this is I’m also machining a matching set of 930 to suby cv axle flanges. No custom axles when mounting a leaf gearbox in vw’s, Porsche’s, bmw’s, Nissan’s, etc.
 

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... Not for nothin', but it doesn't look like it'd be that hard to put a Leaf motor with the reduction gear in the rear of this thing. That would save weight and space for batteries...

It does look there's enough width between the suspension control arms to fit the entire Leaf drive unit, and it would be nice to have it all back there. On the other hand, that subframe would need to be radically altered (or entirely replaced with a custom fabrication) and even without the charger or PDU the unit would be taller, presumably going through the floor. It might make it without the inverter, but the top of this assembly is flat for a reason - it's against the floor.
 

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There’s this project, whom mounted a leaf motor in the rear of a legacy subframe Log into Facebook
View attachment 123510
This Legacy subframe and suspension are not the same as the Impreza, but they are similar enough (as are most recent cars with a driven rear axle and multilink rear suspension) to illustrate the concept. In this case, the front of the subframe was modified - fortunately in the Legacy the trailing control arms apparently don't mount to the subframe, making that easier.
 

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dose the brz use the Impreza rear clip? I would imagine its a slightly different design.

a gen1 motor would be ideal being the inverter and motor don’t creat a seals unit together. I reckon it’s possible, if one is fabrication savy enough.

an mother note, a Lexus gs450h gearbox might be a good fit to try to maintain the original weight distribution.
 

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dose the brat use the Impreza rear clip? I would imagine its a slightly different design.
As far as I know, the BRAT was mechanically a Leone (and in body a modified Leone station wagon); it wasn't like the Golf/Rabbit pickup (Caddy) which had its own suspension. The BRAT was so long ago that it was the Leone, not the later Impreza. The Leone had a basic semi-trailing arm rear suspension.

After the BRAT was the Baja, which was a utility body variant of the Legacy/Outback.

a gen1 motor would be ideal being the inverter and motor don’t creat a seals unit together. I reckon it’s possible, if one is fabrication savy enough.
I agree... and separating the more recent Leaf inverter from the motor has been done.

... a Lexus gs450h gearbox might be a good fit to try to maintain the original weight distribution.
That makes sense. :)
The battery will be heavier than the engine, but if some of the battery can be in the back (replacing the fuel tank, but the shape is really awkward) perhaps a reasonable distribution is possible. In its stock form the BRZ is more front-heavy than this sort of car should be, because the engine and transmission are too far forward.
 

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As far as I know, the BRAT was mechanically a Leone (and in body a modified Leone station wagon); it wasn't like the Golf/Rabbit pickup (Caddy) which had its own suspension. The BRAT was so long ago that it was the Leone, not the later Impreza. The Leone had a basic semi-trailing arm rear suspension.

After the BRAT was the Baja, which was a utility body variant of the Legacy/Outback.


I agree... and separating the more recent Leaf inverter from the motor has been done.


That makes sense. :)
The battery will be heavier than the engine, but if some of the battery can be in the back (replacing the fuel tank, but the shape is really awkward) perhaps a reasonable distribution is possible. In its stock form the BRZ is more front-heavy than this sort of car should be, because the engine and transmission are too far forward.
Spell check got me and changed brz to brat. Yes the EA era cars where all semi Trailing arm rear suspension.
I’ve made longer/wider trailing arms for my brat.
re sealing off the phase connections on a em57 motor isn’t to hard, but a em61 would be the ideal choice.

With the gs450h route, There seems to be plenty of space underneath for modules, so between gas tank location and engine bay, I reckon a pretty slick ev sports car would result. Probably enough space for 50kw of storage, based off Phil’s leaf swapd bzr/86
 

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Spell check got me and changed brz to brat.
Ah... I wondered if you were looking for an alternate rear suspension.
Yes, the BRZ (FR-S, GT86) is essentially a pre-Global Platform Impreza (GJ/GP) in suspension, except:
  • the rear subframe is different to accommodate a different final drive unit (differential), and
  • the front suspension is tweaked quite a bit:
    • control arms are reversed so they extend forward instead of rearward
    • struts are inclined further inward to allow the springs to be lower for a lower hoodline
The rear suspension is very close but possibly not identical (depending on model year) - I checked online OEM parts diagrams and found that some components (e.g. upper control arms, lateral arms) have the same part number for a 2014 Impreza and a 2014 BRZ, while others are slightly different (e.g. knuckles, trailing arms). Some parts (e.g. lower lateral arms) are listed for the Impreza, Forester, and Crosstrek XV.
 

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Discussion Starter · #19 ·
The BRZ was based on a shortened Legacy. You can find photos of its evolution on the internet. As for fitting the motor in the rear subframe, it may be possible but looks at it from underneath it seems like there is not enough room for it to fit. The subframe will be dropped in order to remove the tank; when that happened I can get a photo with the EM57 for comparison.

I can say for sure I will not be using a GS450H motor combo as I already have an EM57. These other custom setups would all drop the manual transmission which is something I wanted to keep with the project.

In terms of progress, I have been slowed by some miscellaneous issues. The CAD work for my motor coupling is in progress along with the charger and DC-DC mounts.
 
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