1986 CRX EV conversion (Nissan Leaf Donor) - Now Running and Misc upgrades

75108 Views 691 Replies 24 Participants Last post by windraver, 24 d ago

windraver

Discussion Starter · Aug 29, 2021 (Edited)

I'm new and am planning to convert my 1986 Honda CRX into an EV. I have a 2015 Fiat 500e for parts but from what I know so far, the Fiat is sensitive and difficult to use for parts. I believe it uses the Bosch 180/120 based on my Google fu. I've sourced the wiring diagram for the vehicle and confirmed it is indeed a 3 phase AC motor, one for each phase, 2 wires to sense temperature, and another 6 for the resolve (excitor, sin, cos). The biggest challenge is that Fiat uses canbus and the controller, inverter, battery, and more likely will not operate without all the parts. The car almost disabled itself when I changed the radio to android auto makes a good example. I am studying how canbus works in order to see if I can either ignore errors or maybe even hack the system to work.

As back up if I have to build from scratch, I have a separate thread pending approval where I'm asking about the compatibility of the Bosch SMG 180/120 with the Scott drive 250 AC controller.

Also I'm reading I might need an inverter? And what else? I'm still digging through the site trying to figure out what are all the parts needed to run an EV with an AC motor, which seems to be more complex and less popular than running DC. So guides or hints are welcome as I learn the anatomy of an EV.
==========
Edit (2021-12-06):
Current project is now to convert the 1986 Honda CRX using a 2013 Nissan Leaf as a donor car in combination with the Resolve-EV Controller.
==========
Edit (2021-12-23):
Project has begun; Battery Dropped; still need a machine shop to make parts.
==========
Edit (2022-07-14):
Car has been running since June 2022. Car has been inspected by the California Referee Station and certified as an EV. DMV has issued registration though they're still trying to figure out internally how to actually label my car as an EV.

My latest work on this build has been to upgrade the battery from 24kwh to 40kwh. Batteries are installed but I still am working out the BMS issues as a bruteforce upgrade doesn't accurately recognize the battery capacity differences.

The to-do list is on-going and always evolving so although the car is running, I'm likely to be doing some new upgrade or change all the time.
==========
Edit (2022-10-23):
Started building a battery box which is the "final battery" box. Still in the planning state but measure many times and cut once.
==========
Edit (2022-12-27):
Battery Box is built and now revising the bus bars and BMS connections to the latest design.
==========
Edit 2023-01-10
Got it running on 2022-12-30. And got it back on the ground and took it on a road test 2022-12-31

Been cleaning up and doing misc upgrades since.

See less See more

Reactions: 3

661 - 680 of 692 Posts

windraver

Discussion Starter · #661 · 2 mo ago

So I checked the wiring diagram and the J1772 Control and Proximity are wired directly the plug that goes to the PDM. It can be disconnected or probed when it's in the Leaf.

I also remembered that I ran these two wires inside the car.

So I looked in a tugged in the wire a bit trying to see if I could reach the plug. It's stuck behind the plastic car trim that covers the fuel spout area.

I decided I'd try to check continuity of both wires from plug to the PDM plug before testing resistance and voltages. But before that, just plug it in to the charger just in case?

And it started charging. So it's probably related to me tugging on the wire/connector for the Control and Proximity wires.

In the meantime I'll let it charge but I definitely will check the wires after I get to 80%.

Separately I came up with a "debugging process" for j1772.

Check if car detects charger plug is connected. If so then proximity is good.
Listen if charger relays activate. If they don't then there's something wrong with Control pilot.
1. Check control pilot wire and continuity from end to end
2. If continuity is good, check voltage, resistance. This should provide the status.

Hopefully that helps someone else (fyi @Electric Land Cruiser )

See less See more

Reactions: 4

kennybobby

· #662 · 2 mo ago

Many times intermittent issues are caused by loose connectors or wiring breaks. Pins and sockets can get oxidation and corrosion built up that interferes with the signals, and the sliding action of disconnection and reconnect wipes them clean.

Reactions: 1

windraver

Discussion Starter · #663 · 2 mo ago

10

Late post but the replacement 12v Lithium battery for Ohmmu came in.

Side by side comparison vs my Optima AGM Yellow top.

Font Gas Electronic device Rectangle Number

Waste container Waste containment Motor vehicle Gas Asphalt

Decided to replace the old battery bracket because it was making it difficult to connect the positive terminal.

Tire Automotive tire Bicycle tire Wheel Bicycle part

Found the Leaf battery bracket which runs the width instead of the length

Safety glove Glove Gas Wood Personal protective equipment

Road surface Bumper Asphalt Gas Automotive exterior

Motor vehicle Automotive exterior Bumper Font Gas

The next immediate challenge was thus the lack of anchor points for the Leaf bracket.

Easily solved with a piece of metal:

Automotive tire Wood Flooring Asphalt Road surface

A quick mock up of where I'll be mounting it with two self taping bolts into the OEM battery mount (that I relocated to the drivers side)

Hood Motor vehicle Automotive design Automotive tire Vehicle

And its mounted!

Motor vehicle Hood Automotive design Vehicle Automotive exterior

Next upcoming mini project is to add a battery maintainer magnetic connector:

Gadget Audio equipment Table Cable Electrical wiring

I found this connector made for the Lotus here:

hethelsport.com

HethelSport | Lotus Evora Specialty

Making great cars better: Aero•Performance•Parts•Accessories

hethelsport.com

There are several connector options available to make it compatible with most float chargers on the market. What makes this "interesting" is that the port, with a cover, to be installed on the car, doesn't engage until the opposing magnetic connector connects. So there isn't a possibility of the to points shorting or something while outside the car. Plus it comes with a fuse. Neat design and makes it easier if the car isn't drive too often.

See less See more

Reactions: 2

Functional Artist

· #664 · 2 mo ago

Is everything back to working as it should? (now)
...especially charging consistently?

Nice work!

I like the (short) cross battery bracket better
...the other (conductive) bracket just seemed like it was a bit too close to the terminals (for me)

Reactions: 1

windraver

Discussion Starter · #665 · 2 mo ago

Functional Artist said:
Is everything back to working as it should? (now)
...especially charging consistently?

Nice work!

I like the (short) cross battery bracket better
...the other (conductive) bracket just seemed like it was a bit too close to the terminals (for me)

It has been charging consistently and I haven't been able to reproduce the issue since tugging on the pilot and proximity wires last time. I still plan to open up and reverify the quality of the connections of those wires but currently, they're working.

I would need to disassemble the interior to check the end to end quality of all the connections so I haven't found time to do that yet.

Reactions: 2

kennybobby

· #666 · 2 mo ago

Would a LiFePO battery ever "need" a float charger-- Does it have a significant self-discharge?

remy_martian

· #667 · 2 mo ago

According to the Google, NMC will self-discharge at 2.5%/month, whereas LiFePO4 will sd at 5% per month.

TL;DR: yes. yes.

windraver

Discussion Starter · #668 · 2 mo ago

kennybobby said:
Would a LiFePO battery ever "need" a float charger-- Does it have a significant self-discharge?

Even if it doesn't self-discharge, I don't drive often and I have plenty of parasitic drain from GPS trackers to Alarm to other things. I'm also planning to explore the OVMS which is an open vehicle monitoring system. The idea is I can monitor and possibly manage my car remotely like the Leaf or Tesla are capable of doing. Maybe even start the car remotely and have it charge the 12v one day. All things to explore.

Reactions: 2

windraver

Discussion Starter · #669 · 2 mo ago

humoring if I want to upgrade the inverter to my swap.

Currently I'm running the 2013 Nissan Leaf motor stack, which is EM57 motor + 80kw inverter + 6.6kw charger (non chademo) paired with the 2018 BMS and 40kwh battery.

80kw inverter is supposedly (110 hp), 280 N⋅m (210 ft⋅lb)

The other inverters in 2018 & 2019+ are:

110 kW (148 hp), 320 N⋅m (240 lb⋅ft)
160 kW (215 hp)

I found a 110kW for $580 dollars which basically means a pretty cheap 38HP increase... I'd probably even consider the 160kW but its generally expensive and not as easy to find (popular Leaf upgrade thanks to Dala)

otherwise I'll just wait until the 2019+ full motor stack gets cheaper or is more readily available. Then I can grab both PDM w/chademo and inverter (currently more expensive or harder to find).

That said, I really need to work on my brakes.

See less See more

Electric Land Cruiser

· #670 · 2 mo ago (Edited)

Check car-parts.com for inverters. I picked up a 160kw inverter for $400ish from a wrecking yard vs. going to ebay. You gotta double check and get photos first because most yards don't know the difference between a charger, inverter, or a motor stack.

But before that you really ought to do some 0-60 and 1/4 mile acceleration runs. I don't think we've seen a video of this thing let loose! I'm sure it will decimate the original 0-60 time.

Reactions: 1

windraver

Discussion Starter · #671 · 2 mo ago

Electric Land Cruiser said:
Check car-parts.com for inverters. I picked up a 160kw inverter for $400ish from a wrecking yard vs. going to ebay. You gotta double check and get photos first because most yards don't know the difference between a charger, inverter, or a motor stack.

But before that you really ought to do some 0-60 and 1/4 mile acceleration runs. I don't think we've seen a video of this thing let loose! I'm sure it will decimate the original 0-60 time.

Thats a good idea. I'll check that.

And it definitely decimated the original time but my tires can't even keep up. peels out for 4-5 seconds until it somehow reaches 20mph and finally takes off. 20-60 is then 3-4 seconds. Which reminds me that the 50:50 weight ratio doesn't help since this is a FWD car. If I could go back in time I would have tried to convince myself to go mid motor like the MR2.

And brakes really need to be upgraded given the weight increase. Going to prioritize my stopping power (for safety) first after thinking about it.

edit: What did you search for to find the inverter? EV parts don't really search well because autowreckers don't really have an option for inverter or PDM.

Reactions: 1

Electric Land Cruiser

· #672 · 2 mo ago

Acura Integra rotors and calipers from the same era bolt on and are a bit beefier.

Reactions: 1

Electric Land Cruiser

· #673 · 2 mo ago

And Integra front a-arms and knuckles for that matter which gives a bit more negative camber and caster.

windraver

Discussion Starter · #674 · 2 mo ago

Electric Land Cruiser said:
Acura Integra rotors and calipers from the same era bolt on and are a bit beefier.

Yea, I put on 1G Integra rotors and calipers. It was good for the CRX but 500 lbs of weight gain probably requires more braking power. Rear are still drums and I would need the whole rear Integra assembly to swap the rear disks over.

kennybobby

· #675 · 2 mo ago

Maybe you could add some weight up front to see if you can get more traction.

Reactions: 1

remy_martian

· #676 · 2 mo ago

500lb of gain? 😬 When did that happen? I thought you kept it inside 100#.

Are you getting fade or need too much pedal force?

The latter might be fixed with swapping in a different booster and master cylinder than the Matchbox-car brake booster you have tucked behind your battery in the recent pic.

A brake pressure sensor to blend in regen would also help if your controller supports it.

windraver

Discussion Starter · #677 · 2 mo ago

remy_martian said:
500lb of gain? 😬 When did that happen? I thought you kept it inside 100#.

Are you getting fade or need too much pedal force?

The latter might be fixed with swapping in a different booster and master cylinder than the Matchbox-car brake booster you have tucked behind your battery in the recent pic.

A brake pressure sensor to blend in regen would also help if your controller supports it.

CRX was originally around 1953lbs and about 2500lbs after the EV conversion.

Motor is lighter but batteries were almost 650 lbs of weight. I'm still lighter than the Leaf by about 1000 lbs but for a car that used to stop on a dime with Integra rotor/pads, it definitely feels like its fully loaded (with batteries).

I'm going to do the electric brake booster swap to replace vacuum booster first and see how it changes. The iBooster is from a CRV and the process will require bleeding the entire brake system. If I still have issues at that point then I'll begin looking into bigger brakes... and might have to even thing about wheels since the current wheels are 14" and the Leaf runs 16" wheels which gives it more room for brake/rotor. Step by step.

Reactions: 1

windraver

Discussion Starter · #678 · 1 mo ago

10

Started the iBooster swap today.

Gas Technology Paint Electrical wiring Flooring

Vacuum pump and switch is out.

Bicycle part Automotive tire Automotive exterior Gas Auto part

Pumped out the brake fluid

Automotive tire Tire Motor vehicle Automotive design Tread

I begin comparing the CRX brake booster and iBooster from the CR-V and I realized, the bolt pattern is the same?!

Automotive tire Automotive design Bumper Automotive exterior Automotive wheel system

Automotive tire Wheel Tire Tread Fender

Lucky me?

Lines are out. Now to unbolt the brake booster from the inside (note it was painful)

Motor vehicle Automotive tire Hood Automotive design Automotive exterior

First thing I tried after getting the CRX booster/MC off was to try to test fit the ibooster

Hood Shotgun Automotive design Motor vehicle Air gun

The bolt pattern fits but the bore of the booster is a tad too big. Some slight grinding of the hole to make it just slightly bigger was enough.

Next problem was the bolts didn't reach. Turns out the ibooster bolts are shorter.

Automotive tire Tread Bumper Coil Automotive wheel system

I also trimmed the top and bottom so it would sit flush

Rim Auto part Metal Bicycle part Titanium

The firewall has a bit of a box in that area so it otherwise wouldn't sit flush.

Motor vehicle Automotive tire Water Automotive design Automotive exterior

to be continued....

See less See more

Reactions: 1

windraver

Discussion Starter · #679 · 1 mo ago

9

continuing...

Next I needed to remove the bolts and put in longer bolts. I don't have a hydraulic press.. but I do have a hydraulic puller? so I just made it work.

Automotive tire Bicycle tire Bicycle fork Bicycle part Bicycle handlebar

And so I removed all 4 bolts.

Automotive tire Bumper Auto part Automotive wheel system Automotive exterior

And found some longer bolts

Automotive tire Gas Electric blue Auto part Automotive wheel system

The welds are ugly but they're solid.

Wood Gas Auto part Metal Machine

Automotive tire Automotive exterior Body jewelry Automotive wheel system Gas

Next off... the clip was a bit... short. So I tried to remove it but I ended up breaking it instead

Tire Automotive tire Glove Tread Bumper

Since I broke it, and it was a centimeter short, I just added a bolt to extend and welded it together.

Automotive tire Wood Gas Auto part Machine

And finally it fits!

Motor vehicle Hood Car Automotive design Automotive tire

Next up, I need to bend the brake lines into position.

Hood Motor vehicle Automotive exterior Auto part Gas

I already have adapters.

What I'm struggling with however is if I need to change the proportioning valve and also add a residual valve.

www.evcreate.nl

Installing the iBooster - EVcreate

Using and installing the iBooster made by Bosch from a used Tesla in your own car can increase breaking performance. There are various ways of mounting it.

www.evcreate.nl

According to the guide, I need both. However the CRX and the Civics, used a diagonal proportioning valve. Meaning that both outputs from the Master Cylinder, go to a proportioning valve that each feeds to Front Left + Rear Right and separately Front Right + Rear Left. This leads me to believe that the residual valve, if any, isn't in the MC. Instead the prop valve handles the rear drum brakes.

So perhaps, I don't need to replace them? Still not certain.

See less See more

Reactions: 4

brian_

· #680 · 1 mo ago

windraver said:
What I'm struggling with however is if I need to change the proportioning valve and also add a residual valve.

Installing the iBooster - EVcreate

Using and installing the iBooster made by Bosch from a used Tesla in your own car can increase breaking performance. There are various ways of mounting it.

www.evcreate.nl

According to the guide, I need both. However the CRX and the Civics, used a diagonal proportioning valve. Meaning that both outputs from the Master Cylinder, go to a proportioning valve that each feeds to Front Left + Rear Right and separately Front Right + Rear Left. This leads me to believe that the residual valve, if any, isn't in the MC. Instead the prop valve handles the rear drum brakes.

So perhaps, I don't need to replace them? Still not certain.

That makes complete sense to me. While all of our CRXs and other Hondas had rear drum brakes, I never changed the braking system configuration so I never had to work out this level of detail.

661 - 680 of 692 Posts