DIY Electric Car Forums banner

Honda CR-Z to E-RZ

29786 Views 40 Replies 10 Participants Last post by  Electric Land Cruiser
Hi guys, I am new to this, sorry if this is in the wrong section but I just wanted to get some thoughts.

I'm 17 and have a huge interest in the future of EVs - in fact I intend to dedicate my life to it. I will be hopefully be attending a top university next year to study mechanical/automotive engineering.

Anyway, on to the point - Call me crazy, but I want to follow in the footsteps of Mate Rimac with his E-M3 and JB Straubel with his homemade EV Porsche. I own a Honda CR-Z (for those that don't know it is a parallel hybrid utilising Honda's IMA technology). As cool as the little gimmicky hybrid is, I want more.

I'm thinking, mini Porsche 918 :D Keep the IMA system and regen braking, but add electric motor/s to power the rear wheels - and if that works, consider going full EV. A fairly ambitious project and hopefully i'll find some like-minded people in uni that would help me undertake it.

Right now though, I do not have the knowhow at all to do this. I thought i'd start small.
They have recently installed Tesla Superchargers right by my home; I would love to turn my HEV into a PHEV. It may seem pointless because the engine charges the battery but i'd love to be able to use the Superchargers hahaa. Also a larger battery would be pretty helpful because a couple of minutes of 'spirited' driving and you run out of electric assistance.
So, in an ideal world, unplug old battery, plug in a bigger battery that you can charge via a supercharger (as well as with the engine preferably); but I know it is not that simple.

Anyone done this before? Anyone going to call me stupid? I'd love to talk more about it and get the thoughts of those who are more experienced.
1 - 20 of 41 Posts

· Registered
Joined
·
70 Posts
I would prefer making the Hybrid more agressive on the road instead of removing the ICE.
In other words try to add Li-Ion or LiFePo4 small pack instead of NIMH cells in the trunk, and make the motor to take bigger portion of the required power in lower revs.
This car is awesome, don't destroy it, just tune the Hybrid portion of that car! :)
 

· Registered
Joined
·
17 Posts
Discussion Starter · #3 ·
I would prefer making the Hybrid more agressive on the road instead of removing the ICE.
In other words try to add Li-Ion or LiFePo4 small pack instead of NIMH cells in the trunk, and make the motor to take bigger portion of the required power in lower revs.
This car is awesome, don't destroy it, just tune the Hybrid portion of that car! :)
Thank you! I do love it, just wish it was MORE of a hybrid, I mean a 14hp motor is noticeable but not exactly 'aggressive' as you say.

I believe a later model has a Li-Ion battery but I don't think it made too much of a difference. I'm not sure how much gain you can get from the stock IMA motor :/

I'm still adamant that an extra say 100kw of electric power to the rear wheels and the manual transmission is a recipe for a lot of fun. I guess the biggest challenge with that is fabricating a way to mount and connect the motors and also how the stock ecu would 'talk' to the controller of the motors.

Many people are focused on tuning the ICE - I just want to go against that completely haha.

So back to the idea of possible little project of a larger capacity battery - what, if anything, would be compatible and how hard would it be?
 

· Registered
Joined
·
70 Posts
Thank you! I do love it, just wish it was MORE of a hybrid, I mean a 14hp motor is noticeable but not exactly 'aggressive' as you say.

I believe a later model has a Li-Ion battery but I don't think it made too much of a difference. I'm not sure how much gain you can get from the stock IMA motor :/

I'm still adamant that an extra say 100kw of electric power to the rear wheels and the manual transmission is a recipe for a lot of fun. I guess the biggest challenge with that is fabricating a way to mount and connect the motors and also how the stock ecu would 'talk' to the controller of the motors.

Many people are focused on tuning the ICE - I just want to go against that completely haha.

So back to the idea of possible little project of a larger capacity battery - what, if anything, would be compatible and how hard would it be?
If you want to make a EV car, prepare 5 digit numbers($) in your pocket for >100kW of power, and a lot of reverse engineering on the car.
The option for making CR-Z more responsive is to make the battery Li-ion, for example these cells are about 0,5kg each, you need 36 cells to make the car more responsive for longer periods of time, with lighter battery in the trunk. The biggest problem here will be to lie the ECU with the new battery(internal resistance make electronics go crazy) but not impossible. :)
 

· Registered
Joined
·
17 Posts
Discussion Starter · #5 ·
If you want to make a EV car, prepare 5 digit numbers($) in your pocket for >100kW of power, and a lot of reverse engineering on the car.
The option for making CR-Z more responsive is to make the battery Li-ion, for example these cells are about 0,5kg each, you need 36 cells to make the car more responsive for longer periods of time, with lighter battery in the trunk. The biggest problem here will be to lie the ECU with the new battery(internal resistance make electronics go crazy) but not impossible. :)
Guess i'd just look into it more if i were to really consider it. Just had this picture in my head of going to a breakers yard, pulling a a motor or two out of hybrid lexus or something (rx400h, 67hp motor) as well as knicking the battery out of it, getting a good deal, buying an off-the-shelf controller and whacking it all together.

I look at the 918, new NSX and other performance series/parallel hybrids and think 'how hard can it be to copy that drivetrain'? I forget that these companies have multi-million dollar R&D budgets :/
 

· Administrator
Joined
·
6,613 Posts
Hi Lloyd
You can do it!
Assuming that you are willing to lose the back seat I would say that you can do that for a much lower budget (5,000 pounds - ish)

I would be thinking about getting hold of a crashed Nissan Leaf,
Install the motor/trans-axle of the leaf in the back of your Honda
The Leaf battery would have to be disassembled and rebuilt in smaller modules to fit anywhere where there was space

Issues -
Getting the Nissan controller to work in it's new home - either keep enough of the Nissan bits so it thinks it's still in the Leaf
Or replace the control board with a new one
Both of these strategies are used by people on this forum

Integrating it with the Honda
You could keep the two completely separate - they don't need to talk to each other people used to build "Twini" mini's - a mini with an engine at each end
Leyland even made a twini Moke which they tried to sell as a Jeep to the Canadian Army

Or you could throw away the dino burner and all of it's ancillary junk - exhausts, fuel tanks.....

One problem
Tesla Superchargers are for Tesla's - you may not be able to use them
 

· Registered
Joined
·
17 Posts
Discussion Starter · #7 ·
Hi Lloyd
You can do it!
Assuming that you are willing to lose the back seat I would say that you can do that for a much lower budget (5,000 pounds - ish)
Thank you so much! The more I look into this project the more I want to do it, it excites me so much

I would be thinking about getting hold of a crashed Nissan Leaf,
Install the motor/trans-axle of the leaf in the back of your Honda
The Leaf battery would have to be disassembled and rebuilt in smaller modules to fit anywhere where there was space
This is what I was thinking, surely I could find motors and a battery from a crashed hybrid or EV and use those. Would be much cheaper than an off-the-shelf motor, controller and battery

You could keep the two completely separate - they don't need to talk to each other people used to build "Twini" mini's - a mini with an engine at each end
Leyland even made a twini Moke which they tried to sell as a Jeep to the Canadian Army
Again, I was just thinking about this, why would them being separate be a problem? I was even thinking about keeping the stock battery too, I don't really want to mess with the stock IMA system and the regen braking unless I could get the regen braking to work with the new battery - is that possible?

Tesla Superchargers are for Tesla's - you may not be able to use them
You may be right - looking into it, even some teslas can't use them as supercharging was an optional extra! It says 'free electric vehicle charge point' above them so i just assumed it meant all EVs haha, there are still other public charge points around though right?
 

· Administrator
Joined
·
6,613 Posts
I don't really want to mess with the stock IMA system



Hi Lloyd
That statement worries me a bit - while I think you CAN do the sort of conversion you fancy and for a reasonable sum

It is NOT going to be simple! - it will take a lot of "buggering about' to make the whole thing work
It will take a lot of work to make it FIT! in that small car
(which is why I recommend dumping the dino burner and all its ancillaries)



Nothing that ingenuity and hard work can't fix - but its not going to be easy
 

· Registered
Joined
·
17 Posts
Discussion Starter · #10 ·


That statement worries me a bit - while I think you CAN do the sort of conversion you fancy and for a reasonable sum



I just sort of meant that the stock IMA system for recharging the battery is a great system and I didn't want to get rid of the integrated motor and still wanted to utilise the regenerative braking system that the car already has.

I'm completely serious about this project though, it would be so much fun to learn through university, and at first glance, I think I have the finances to do it.

Maybe one day i'll ditch the dino burner ;) make it a 4wd EV and get into torque vectoring and all that cool stuff! As much as I love the economic benefits of going all electric, power and fun is the goal here for me :D I mean look at the Rimac Concept_One...
 

· Registered
Joined
·
324 Posts
In theory adding electric drive to the rear wheels to have an instant plugin hybrid sounds great. If you think of it as adding a second gas engine, plus ancillaries and another gas tank, but worse (in terms of weight and volume) you might start to get why this is harder than it sounds. Most EV conversions benefit hugely from removing all the ICE related gear to free up space and reduce weight.

You could add a smaller/lighter hybrid motor perhaps more easily, but many of them are fully integrated into a package that makes them big/heavy for their power as electric motors go. There are a few electric RWD motors out there from production hybrids (lexus or the new RAV4 perhaps) used to make an "AWD" hybrid that might be promising. Decent power, pretty small/light, etc. But without a bigger battery you'll only be giving yourself a one time boost of maybe 60s or so worth of power, unless you can find a way to integrate it into the rest of the hybrid system and recharge in a way that doesn't kill efficiency.

Adding a full EV system from a Leaf would be great for power and range, but now you are talking about adding ~750-1000 lbs of gear which aside from difficulty probably won't do a lot for your handling/performance.

Using the Leaf system or equivalent to replace the CRZ drive system completely should give a pretty nice bump in performance and range over the heavier / higher CdA stock Leaf. I'd love to see someone try a dual Leaf AWD setup on a small platform like this! That would probably be a real kick in the pants ;)

Rob
 

· Registered
Joined
·
17 Posts
Discussion Starter · #12 ·
In theory adding electric drive to the rear wheels to have an instant plugin hybrid sounds great. If you think of it as adding a second gas engine, plus ancillaries and another gas tank, but worse (in terms of weight and volume) you might start to get why this is harder than it sounds. Most EV conversions benefit hugely from removing all the ICE related gear to free up space and reduce weight.

You could add a smaller/lighter hybrid motor perhaps more easily, but many of them are fully integrated into a package that makes them big/heavy for their power as electric motors go. There are a few electric RWD motors out there from production hybrids (lexus or the new RAV4 perhaps) used to make an "AWD" hybrid that might be promising. Decent power, pretty small/light, etc. But without a bigger battery you'll only be giving yourself a one time boost of maybe 60s or so worth of power, unless you can find a way to integrate it into the rest of the hybrid system and recharge in a way that doesn't kill efficiency.

Adding a full EV system from a Leaf would be great for power and range, but now you are talking about adding ~750-1000 lbs of gear which aside from difficulty probably won't do a lot for your handling/performance.

Using the Leaf system or equivalent to replace the CRZ drive system completely should give a pretty nice bump in performance and range over the heavier / higher CdA stock Leaf. I'd love to see someone try a dual Leaf AWD setup on a small platform like this! That would probably be a real kick in the pants ;)

Rob
Thanks for your reply! Well the leaf powertrain is 80kw (108hp). The CR-Z is 1198kg and has 123hp, a power to weight ratio of 102hp/metric ton. So with a quick calculation, the whole new system would need to weigh less than 1042kg (2300lbs) to be somewhat beneficial to performance. Upon quick research, the leaf battery and charger/inverter/motor assembly weigh a total of 423kg (932lbs)

New power to weight ratio would be 143hp/metric ton. Looking at that you think is it even worth it with how much it'll destroy the handling of the car.

The deeper I go into this the more naive and ignorant I realise I am. I feel like I need to meet an electrical engineer, a software engineer and be studying mechanical engineering myself to be able to do this :D

The reason I wouldn't want to go full EV (yet) is because I'm only 17, it's an expensive car (for me) and also my daily car that I need to keep on the road. I'd need to get to a stage where it could run electric only as a hybrid and then rip out the ICE when i'm comfortable with how the electric part is working.

Off topic:
In case you guys didn't know, the CR-Z is being discontinued for next year :( maybe if honda did what i'm trying to do in the first place it would've been more of a hit hahaa. (Guess that's what the new NSX is, just A LOT more expensive)
 

· Registered
Joined
·
57 Posts
Since you want power and performance over anything else I'd suggest you go with a DC system. Since this is your only car I would suggest starting on a second beater car. It may be more cost effective in the long run and will let you keep the crz on the road.

Adding rwd to a fwd car will involve making a custom rear sub frame and probably having to move/customize things like the exhaust, fuel tank and IMS battery.

By going the route of a second car you can build a working EV system with components that can easily be moved into another car once you get everything sorted out.

Honda's are known for being easy to swap other Honda motors into due to a lot of parts sharing similar drive shafts. You could easily start with a D or B series older ICE Honda and when the time comes the only fabrication you would have to do to move it to the crz would be making new mounts and adapting the shifter and drive shafts.

I did a quick search and the only engine swap crz I could find was a K20. I don't know of an existing motor adapter for an ev motor to a K20 but they are available for D and B series at canev.com. You can also make your own, and you can probably do it with the stock crz motor although that would mean lots of time off the road. Another option is to buy a second crz tranny and mount up the motor first, get a controller and pack pre wired and running outside of the car so when it comes to actually putting it in the car you could probably do it in a solid weekend of hard work, maybe less with help.


Unless you plan to be really fast above 80mph think torque more than kW or hp. An 80kW motor with 200ftlbs like the leaf would be mighty fun driving around town and very capable on the highway. The leaf rating is also said to be continuous. There's someone building an inverter for it that I think said it should be able to handle peak of 200kW.
 

· Registered
Joined
·
17 Posts
Discussion Starter · #14 ·
Since you want power and performance over anything else I'd suggest you go with a DC system. Since this is your only car I would suggest starting on a second beater car. It may be more cost effective in the long run and will let you keep the crz on the road.

Adding rwd to a fwd car will involve making a custom rear sub frame and probably having to move/customize things like the exhaust, fuel tank and IMS battery.

By going the route of a second car you can build a working EV system with components that can easily be moved into another car once you get everything sorted out.

Honda's are known for being easy to swap other Honda motors into due to a lot of parts sharing similar drive shafts. You could easily start with a D or B series older ICE Honda and when the time comes the only fabrication you would have to do to move it to the crz would be making new mounts and adapting the shifter and drive shafts.

I did a quick search and the only engine swap crz I could find was a K20. I don't know of an existing motor adapter for an ev motor to a K20 but they are available for D and B series at canev.com. You can also make your own, and you can probably do it with the stock crz motor although that would mean lots of time off the road. Another option is to buy a second crz tranny and mount up the motor first, get a controller and pack pre wired and running outside of the car so when it comes to actually putting it in the car you could probably do it in a solid weekend of hard work, maybe less with help.


Unless you plan to be really fast above 80mph think torque more than kW or hp. An 80kW motor with 200ftlbs like the leaf would be mighty fun driving around town and very capable on the highway. The leaf rating is also said to be continuous. There's someone building an inverter for it that I think said it should be able to handle peak of 200kW.
I did think about that, I was thinking of abandoning the cr-z idea completely and buying an old mx-5 - literally about $1000 here in the uk - declaring it off the road and converting that!

But I just loved the original ethos of the cr-z being probably the world's first fun hybrid and wanted to take it further. I began to slightly dissect my car and you're right, getting drive to the rear wheels is not going to be simple at all.

That's a good idea though, I never thought of a sort of 'trail run' so that when it comes to the real thing there's less time off the road and I vaguely know what I'm doing.

So much to consider :eek: wow I want to do this so badly. Feels like there's a million barriers to break through though - mechanically, mentally, legally and financially :p
 

· Registered
Joined
·
17 Posts
Discussion Starter · #15 ·
Can anyone enlighten me on 'compatibility'?

Scavenging for parts from crashed EVs/HEVs seems like a much more cost effective option, but how hard - if even possible - is it to make different components work together? :confused: For instance, a motor or two from a leaf, a battery from another manufacturer... etc. I feel like it could never work, and fundamentally I still don't understand how controllers control it all.
But off the shelf components are sooo expensive :(

Keeping it simple, all I really want is 1 or 2, cheap but powerful motors that mimick's what the ECU tells the stock motor on the engine to do. What battery capacity would be sufficient for these new motors but also work with the stock motor? The stock battery is rated at 5.75Ah, that's minisule isn't it. :( Not particularly bothered if the battery runs out after one or two 0-60 launches. (well, that's is the bare minimum of what I want to get out of this project)
 

· Registered
Joined
·
57 Posts
Have you driven a miata? Oh my god the miata.... so nice. I miss mine. I sold it for $1300 because it had a leaking gas tank and the subframe bolts looked like they may break if you dropped the frame to fix it. The perfect ev project before i even knew i wanted to do one. I miss the way that car drives. If you are thinking of doing the miata do it! I've only test driven the crz but it was no where near the car the miata is. It's just so pure and light and handles so well. There's a decent size trunk for batteries but if you also have the crz range isn't as much an issue.

Out of a 91 skyline gtr, miata, alfa spider, 02 mini cooper s, motor bikes and all the non sporty cars i have had I miss the miata the most. I like the crz and have thought about it as an ev but it isnt in the same league. It's a honda fit with a sporty body.

You should look into used forklift motors on this site and paul and sabrinas diy motor controller. 144v 500 amps 72kW for around $1000 is pretty cheap if you're willing to learn about it. That should move a miata well. You can also upgrade in stages from there. First a warp or kostov motor or a used adc9 if you can find one then a more powerfull controller and you can double those numbers when you save up £ with minimal time off the road.
 

· Administrator
Joined
·
6,613 Posts
Hi Lloyd
Mixing and matching modern car parts is no longer easy
Even parts from the same manufacturer and model may take the hump and refuse to cooperate with each other
Not just EV parts some of my pals have been unable to get different gearboxes to work in the "wrong" car

You can
Go DC - cheap cheerful and powerful
But a bit primitive - not a good match for your Honda bits
Great in a Miata!

Use all of the parts from something like a leaf

Use the expensive power electronics from some modern cars and substitute a new "brain board" on top

Buy "new" AC power bits - expensive and a bit wimpy

That does not include batteries - second hand batteries from a Volt or Leaf are by far your best bet
But you may not be able to get the BMS working
 

· Registered
Joined
·
17 Posts
Discussion Starter · #18 ·
Have you driven a miata? Oh my god the miata.... so nice. I miss mine. I sold it for $1300 because it had a leaking gas tank and the subframe bolts looked like they may break if you dropped the frame to fix it. The perfect ev project before i even knew i wanted to do one. I miss the way that car drives. If you are thinking of doing the miata do it! I've only test driven the crz but it was no where near the car the miata is. It's just so pure and light and handles so well. There's a decent size trunk for batteries but if you also have the crz range isn't as much an issue.

Out of a 91 skyline gtr, miata, alfa spider, 02 mini cooper s, motor bikes and all the non sporty cars i have had I miss the miata the most. I like the crz and have thought about it as an ev but it isnt in the same league. It's a honda fit with a sporty body.

You should look into used forklift motors on this site and paul and sabrinas diy motor controller. 144v 500 amps 72kW for around $1000 is pretty cheap if you're willing to learn about it. That should move a miata well. You can also upgrade in stages from there. First a warp or kostov motor or a used adc9 if you can find one then a more powerfull controller and you can double those numbers when you save up £ with minimal time off the road.
I have never driven one, but I would own one if it wasn't for the insanely high insurance here in the UK (No idea how I got insured on the CR-Z). Tempting me with the miata build ;) The only problem is space, barely enough room for 1 of my cars on the drive haha.

I do get that the CR-Z is pretty flawed and a bit of a gimmick, and thats why i really wanted to improve it and make it great - maybe one day. Who knows what is to come from all this speculation.
 

· Registered
Joined
·
17 Posts
Discussion Starter · #19 ·
Hi Lloyd
Mixing and matching modern car parts is no longer easy
Even parts from the same manufacturer and model may take the hump and refuse to cooperate with each other
Not just EV parts some of my pals have been unable to get different gearboxes to work in the "wrong" car

You can
Go DC - cheap cheerful and powerful
But a bit primitive - not a good match for your Honda bits
Great in a Miata!

Use all of the parts from something like a leaf

Use the expensive power electronics from some modern cars and substitute a new "brain board" on top

Buy "new" AC power bits - expensive and a bit wimpy

That does not include batteries - second hand batteries from a Volt or Leaf are by far your best bet
But you may not be able to get the BMS working
Thanks! I get that electronics really isn't just off-the-shelf plug-and-play, doing something so niche as converting a car's powertrain is never going to be simple. But I guess that's what I love about it; people are still caught up on making they're cars fast with forced induction - what is this 1890? I want electrons! :cool:
 

· Registered
Joined
·
324 Posts
It's not quite plug and play simple, but there is a certain amount of component re-use experimentation going on. Batteries from a Leaf or Volt are quite popular bang/$ wise, and in some situations you can even retain the BMS. I believe the Chevy chargers have also been reverse engineered to work pretty well stand alone. There are several promising inverter/controller builds going on that should have the ability to auto-tune to many OEM motors, such as Leaf, Lexus or even Tesla.

As Duncan mentioned another strategy is to try and use enough parts from one OEM car to make it still work as originally intended in another platform. There are several folks trying this with wrecked gen 1 and 1.5 Leafs.

Rob
 
1 - 20 of 41 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top