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Discussion Starter #1 (Edited)
It's likely that I'll begin restoring a 1966-1977 Ford Bronco this year. It's increasingly likely that I'll try and put an electric motor in it. Talk me out of it.

I'm confident in my ability to take the truck apart to the frame and put it back together. I'm not confident in my ability to put a reliable electric drivetrain in it, nor do I know what I'm talking about with regard to components and the complexity involved in installing those components.

I've done some research, and tried to read the wiki and sticky threads, but a lot of the info I'm finding is from ten years ago. Now that people are crashing Leafs and Teslas, the equations have changed. Seemed like a starting a thread, even if I'm doomed to failure, is a good step at this point.

Goals
Mostly to finish and have an enjoyable car to bump around the city with. In stock trim, the most anemic Bronco rolled off the floor with a 170cc I6 that put out 156 ftlb of torque, and 100hp. As mine will have 31-35" tires, I'm calling this the bare minimum in terms of acceleration potential. The more the merrier.

A 50mph top speed would probably do me...75mph would be lovely.

50 miles of range would do it for me, but of course, the more the merrier.

Gearing
In stock trim, with a 4.56 final drive and 3.41 first gear, the little six put ~2400 ftlb of torque to the axles. If you look, you can find a Dana 60 or Ford 9" with monstrous 7:1 gearing, but that's still about half the reduction I would need to do direct drive with a single electric motor. I think. I just multiplied torque by the various gear reductions.

Directish-drive would be doable with a monster Tesla motor, but it seems like the better bet would be to keep the transmission (which gives me near infinite gearing options). This also allows me to keep the transfer case, and thus, 4WD which is pretty cool. Indeed, I don't even know how I would remove the front axle to save weight.

I expect to use a clutch, because I'm used to it.

Amenities
• Bikini top, at most. Everything needs to be protected from rain and theft.
• Very heated seats.
• Regenerative breaking for the stop and go, hills etc...
• Power steering, I think. They didn't all have them, but they didn't all have monster tires.
• Boosted brakes.
• 1000W stereo. Well. Maybe.
• Standard charge port at 240V, but this can be deferred.

Batteries
It seems like, and correct me if I'm wrong, the bang-for-buck is to salvage a full pack from a crashed Nissan Leaf or Tesla Model S. How hard is it to take these packs apart and repurpose the individual packs? My napkin numbers:

Leaf pack - 24 kWh - $4k - 170 $/kWh
Tesla pack - 75 kWh - $15k - 200 $/kWh

The Tesla pack has a significant advantage of weight and density, which is always nice.

To what degree should I be concerned about voltage? Is that something I can change to suit by varying series and parallel wiring?

The first place I'm likely to skimp is the battery pack, operating on the assumption that it would be easiest to swap out for a better one down the road. Technology is improving rapidly here, and costs are coming down quick.

Motor
I've read that, in 2019, AC is just the way to go. Less compromises. With that in mind, the bang-for-buck that I'm seeing is the NetGain HyPer 9.

Tesla Model S - $12k - 325 ftlb
NetGain HyPer9 - $4300 - 162 ftlb
Curtis AC50 - $4850 - 120 ftlb

The Tesla seems to have a built-in reducer, which could be nice, but...I'm just guessing it will be easier to adapt a cylinder to the stock transmission. I'm not sure I'm ready to go $12k motor direct to the rear diff on my first attempt at building an electric car.

AC motors seem to come with built in controllers, so I think I'm done there.

Considerations
• Adapt the motor to the transmission, preferably with dedicated mounts.
• Build a home for the batteries in the bed or just...kind of...stash them around the chassis as low and centered as is practical.
• Electric throttle pedal.
• Electric brake booster. Dunno how easy it is to get the balance right.
• Electric power steering. Dunno how this would work on a Ford steering box yet.
• High voltage wiring.
• 2000w(?) converter to power 12V systems and small AGM battery.
• Some kind of screen for gauges.
• Some way to charge the batteries.
• BMS seems wise. I want to set this truck up, and then not mess with it. No fires.

Cost
$5k for a small battery pack.
$10k for a large battery pack (sell off part of a Tesla pack).
$5k for the motor and controller.
$5k for realism, wiring, adaptors, some professional labor...

So Maybe $15k?

What is the largest thing I'm missing?

 

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Gearing

Gearing
In stock trim, with a 4.56 final drive and 3.41 first gear, the little six put ~2400 ftlb of torque to the axles. If you look, you can find a Dana 60 or Ford 9" with monstrous 7:1 gearing, but that's still about half the reduction I would need to do direct drive with a single electric motor. I think. I just multiplied torque by the various gear reductions.
Good start, but did you consider the road speed range that would give you? You can't rationally choose gearing without knowing something about what motor you are using, since they have different top speeds and speeds for maximum power output. Specific tire diameter matters too, of course. If you use even 7:1 gearing with a low-speed motor, your top speed will be limited. How much gear reduction you need depends on the motor.
 

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Batteries

Batteries
It seems like, and correct me if I'm wrong, the bang-for-buck is to salvage a full pack from a crashed Nissan Leaf or Tesla Model S. How hard is it to take these packs apart and repurpose the individual packs? My napkin numbers:

Leaf pack - 24 kWh - $4k - 170 $/kWh
Tesla pack - 75 kWh - $15k - 200 $/kWh

The Tesla pack has a significant advantage of weight and density, which is always nice.

To what degree should I be concerned about voltage? Is that something I can change to suit by varying series and parallel wiring?
Back to the theme of evolving component choices...
  • there are now other salvage options from other EVs (although original Leaf and Tesla Model S/X are the most common) including newer Leaf (40 kWh), and
  • you can buy a complete new 60 kWh Chevrolet Bolt battery for less than the price of that used Tesla pack.

All batteries are composed of multiple modules, and modules can usually be reconfigured to change operating voltage. Whether or not this is an issue depends on your combination of battery choice and motor choice.
 

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Motor

Motor
I've read that, in 2019, AC is just the way to go. Less compromises. With that in mind, the bang-for-buck that I'm seeing is the NetGain HyPer 9.

Tesla Model S - $12k - 325 ftlb
NetGain HyPer9 - $4300 - 162 ftlb
Curtis AC50 - $4850 - 120 ftlb

The Tesla seems to have a built-in reducer, which could be nice, but...I'm just guessing it will be easier to adapt a cylinder to the stock transmission. I'm not sure I'm ready to go $12k motor direct to the rear diff on my first attempt at building an electric car.

AC motors seem to come with built in controllers, so I think I'm done there.
There is no point in comparing torque without considering speed. The production EV motor are intended for much higher voltage than the aftermarket motors, and can produce their torque at higher speeds (more power).

Any motors salvaged from a modern production EV will be used in the original EV with a transaxle containing single-ratio reduction gearing and a differential, and that transaxle is typically included in units for sale. It seems Tesla Model S/X motors always come with the transaxle, because the motor is not readily separated from it. It would be hard to use this sort of transaxle in the Bronco, because the reduction gearing is not in a separate case from the differential. One interesting setup uses the left and right axle outputs of the salvaged drive unit (motor plus transaxle) to drive the shafts to the Bronco's front and rear axles (instead of using the Bronco's transfer case), but the overall gear reduction ratio would be excessive.

Motors salvaged from a modern production EV are all AC, and are commonly available with the controller/inverter, which is often packaged closely with the motor. Aftermarket AC motors (such as the HyPer9 and AC50) may be sold in a package with a controller/inverter, but they are two separate components, usually separately priced.

If you really want a high-torque motor suited for use with only the ring-and-pinion gearsets in the Bronco's axles for reduction gearing, the Chevrolet Spark is an interesting choice: it is designed for use with less than 4:1 reduction (with Spark-sized tires).
 

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It's likely that I'll begin restoring a 1966-1977 Ford Bronco this year...
Looking good! I assume that the restoration to come is mechanical, rather than body... or that's someone else's Bronco for illustration of the type of vehicle and target look.
 

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It's likely that I'll begin restoring a 1966-1977 Ford Bronco this year. It's increasingly likely that I'll try and put an electric motor in it. Talk me out of it.

I'm confident in my ability to take the truck apart to the frame and put it back together. I'm not confident in my ability to put a reliable electric drivetrain in it, nor do I know what I'm talking about with regard to components and the complexity involved in installing those components.

I've done some research, and tried to read the wiki and sticky threads, but a lot of the info I'm finding is from ten years ago. Now that people are crashing Leafs and Teslas, the equations have changed. Seemed like a starting a thread, even if I'm doomed to failure, is a good step at this point.

Goals
Mostly to finish and have an enjoyable car to bump around the city with. In stock trim, the most anemic Bronco rolled off the floor with a 170cc I6 that put out 156 ftlb of torque, and 100hp. As mine will have 31-35" tires, I'm calling this the bare minimum in terms of acceleration potential. The more the merrier.

A 50mph top speed would probably do me...75mph would be lovely.

50 miles of range would do it for me, but of course, the more the merrier.

Gearing
In stock trim, with a 4.56 final drive and 3.41 first gear, the little six put ~2400 ftlb of torque to the axles. If you look, you can find a Dana 60 or Ford 9" with monstrous 7:1 gearing, but that's still about half the reduction I would need to do direct drive with a single electric motor. I think. I just multiplied torque by the various gear reductions.

Directish-drive would be doable with a monster Tesla motor, but it seems like the better bet would be to keep the transmission (which gives me near infinite gearing options). This also allows me to keep the transfer case, and thus, 4WD which is pretty cool. Indeed, I don't even know how I would remove the front axle to save weight.

I expect to use a clutch, because I'm used to it.

Amenities
• Bikini top, at most. Everything needs to be protected from rain and theft.
• Very heated seats.
• Power steering, I think. They didn't all have them, but they didn't all have monster tires.
• Boosted brakes.
• 1000W stereo. Well. Maybe.
• Standard charge port at 240V, but this can be deferred.

Batteries
It seems like, and correct me if I'm wrong, the bang-for-buck is to salvage a full pack from a crashed Nissan Leaf or Tesla Model S. How hard is it to take these packs apart and repurpose the individual packs? My napkin numbers:

Leaf pack - 24 kWh - $4k - 170 $/kWh
Tesla pack - 75 kWh - $15k - 200 $/kWh

The Tesla pack has a significant advantage of weight and density, which is always nice.

To what degree should I be concerned about voltage? Is that something I can change to suit by varying series and parallel wiring?

The first place I'm likely to skimp is the battery pack, operating on the assumption that it would be easiest to swap out for a better one down the road. Technology is improving rapidly here, and costs are coming down quick.

Motor
I've read that, in 2019, AC is just the way to go. Less compromises. With that in mind, the bang-for-buck that I'm seeing is the NetGain HyPer 9.

Tesla Model S - $12k - 325 ftlb
NetGain HyPer9 - $4300 - 162 ftlb
Curtis AC50 - $4850 - 120 ftlb

The Tesla seems to have a built-in reducer, which could be nice, but...I'm just guessing it will be easier to adapt a cylinder to the stock transmission. I'm not sure I'm ready to go $12k motor direct to the rear diff on my first attempt at building an electric car.

AC motors seem to come with built in controllers, so I think I'm done there.

Considerations
• Adapt the motor to the transmission, preferably with dedicated mounts.
• Build a home for the batteries in the bed or just...kind of...stash them around the chassis as low and centered as is practical.
• Electric throttle pedal.
• Electric brake booster. Dunno how easy it is to get the balance right.
• Electric power steering. Dunno how this would work on a Ford steering box yet.
• High voltage wiring.
• 2000w(?) converter to power 12V systems and small AGM battery.
• Some kind of screen for gauges.
• Some way to charge the batteries.
• BMS seems wise. I want to set this truck up, and then not mess with it. No fires.

Cost
$5k for a small battery pack.
$10k for a large battery pack (sell off part of a Tesla pack).
$5k for the motor and controller.
$5k for realism, wiring, adaptors, some professional labor...

So Maybe $15k?

What is the largest thing I'm missing?



Hello!

I had a 71 Bronco that I had been planning to convert (it ended up traded away for work on my house that has yet to happen.. we will see) to electric.

My plan involved changing the transmission out to an *NP435 4 speed because I planned to use an AC motor. The first gear on the tranny was a 6.68 and more importantly the Reverse gear is around 8.26.
My reasoning here is that an AC motor can be electrically reversed, and the transmission put into reverse as an additional low forward gear. All of my napkin math put the change in low gears as a bump from 51-1 for 1st gear up to 65-1 by shifting in reverse/reverse (assuming stock Dana 20 low range and 4.10 gears).

*http://www.novak-adapt.com/knowledge/transmissions/manual/np435

To accommodate the NP435 swap, there are conversion kits on https://www.wildhorses4x4.com/product/NP435_T18_to_dana20_Adapter/Bronco_Transmission_Adapters As an example, you can also get them from other Bronco parts retailers, this was just the first one that popped into my head.

To mount the motor to the transmission I would have attached a Small Block Ford Bellhousing to the NP435 and then procured a transmission adapter plate like this one: https://www.evwest.com/catalog/prod...ucts_id=140&osCsid=jblii9b6v2dghov4cb0i7vofn4

My plan for the Power Steering was heading towards something like this connected to the manual steering box:
https://www.evwest.com/catalog/prod...ucts_id=363&osCsid=jblii9b6v2dghov4cb0i7vofn4

I had been looking at the Marine liquid cooled version of the HPEVS dual motors as a potential motor, but now I would probably just go with the Netgain AC motor.

I would encourage you to checkout “Tipover’s” Electric Suzuki Samurai, as it is a very well done AC conversion in the same manner that you want to do.
He used an HPEVS AC31 motor and Chevy Volt batteries to build a rig that he has taken up the Rubicon. I believe that it is on 33” tires now.

Hopefully, you can just search for his threads here. Also, you can look for his videos on YouTube. And he also has a thread on Pirate 4x4 if you are interested.
 

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Discussion Starter #9 (Edited)
This is all very helpful.

Current plan is to attach a motor to a transmission and use the whole stock drivetrain. That way, my gearing choices are numerous without much hassle, and would allow for 4WD which is always nice to have in a small monster truck.

The HyPer9 motor (according to a janky image—it's hard to find real specs for this thing) makes peak torque until about 2500rpm after which it dwindles, and then begins a steep decline at about 3500rpm. This is right about the range of an old American truck engine, so I expect ratios would be well within range of what's possible with transmission swaps and aftermarket gears. It's a wild idea to repurpose reverse! That's nifty.

Is there a good resource for comparing OEM drivetrains? Assuming I just need to rig up motor mounts and shaft/bellhousing adapters, would it be better bang for buck to try and go with a salvaged motor...? I don't know my Leaf from my Bolt at this point. I fear some of them require hacking of controllers and emulation of ECUs and what not...I tend to prefer standard components, unless there is real gain in repurposing.

Unfortunately, that image is just a placeholder. I'm beginning my search for a good chassis presently, and it will be uglier.

Out of curiosity, where would the other $15k that I'm not accounting for be spent?

That Samurai is a sweet install:

https://www.pirate4x4.com/forum/general-4x4-discussion/2195009-zookev-electric-suzuki-samurai.html

https://www.diyelectriccar.com/forums/showthread.php/zookev-156817.html

One thing he did that I might was to use cheap lead-acid batteries until he got the thing sorted (after which he went with a Volt battery). That said, it may not be worth trying to procure and then sell a bunch of cheap batteries, so maybe I'll just buy them last...

Time to read through that LandRover three...I wish more pics had survived.
 

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Unless you go with a drivetrain that has already been reverse engineered for DIY conversion, you have a huge uphill battle in repurposing the OEM motors and VFD’s.
Even if you use one of the”kit” DIY AC motor controllers to spin the motor, there is still a lot more technical detail work that you need to do to get them running.

Unless things have changed in the year or so that I have been mostly inactive here, the DIY AC controllers were really more of a hobby for electrical engineers with lots of spare time.

You could probably **Buy a commercial Variable Frequency Drive from EV West that will spin an OEM AC motor, but they tend to run around the same price for just the VFD as just buying an HPEVS or Netgain Hyper 9 would cost you.
Then, you still have to figure out how to attach the OEM motor to the transmission.

I “feel” that your time would be more productively spent not reinventing the wheel.

The Hyper 9 and the HPEVS motors have both been engineered around the constraints of the Warp 9 motor for which there is a plethora of transmission attachment plates left over from earlier conversions (I mean in stock at EV conversion supply stores online) which makes the motor attachment phase a bolt on affair.

This still leaves the motor mounts to the frame to fabricate, but comparatively, that can be a rougher product and still work, whereas adapting the motor to the transmission requires finer tolerances because of the high torque and balance issues. When you are spinning your drivetrain up to 2,500 RPM at 170 ft lbs, you don’t want a micro wobble in between your motor and your transmission while you are driving up a stack of rocks... in my opinion.

I am simply putting forth my own reasons for the design choices that I made, if you are an electrical engineer or rich or both, don’t let me dissuade you from living your life how you want to. :cool:

** https://www.evwest.com/catalog/prod...ucts_id=293&osCsid=1av0k53mlsleqatlp5bm1io986

https://www.evwest.com/catalog/prod...ucts_id=262&osCsid=1av0k53mlsleqatlp5bm1io986

These are simply examples of commercial VFD’s available, I don’t know whether they would run an OEM motor.
 

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I would look at using the Netgain AC motor package and then put this 2:1 converter behind it connected to the transfer case.


https://www.torquetrends.com/


This should allow you to keep all the stock drivetrain and have a nice AC motor package to drive it that does not break the bank like a Tesla motor solution.
 

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Discussion Starter #12
I'm not looking to build the cheapest EV I can, but I'm also not looking for a high performance monster. I'm trying to ride the wave of bang-for-buck while taking into account my skills (mechanical, electrical, software) and weaknesses (fabrication...specific knowledge of electric automotive drivetrains). I plan for this to be a daily driver in a traffic-ridden city, with occasional overland use for fun.

I'm still at least months out, as I plan to restore as I convert. I migth try to get it going fully electric to make sure I can actually do it, then take everything apart, but I'm not confident I'll want to take anything apart once I have a running machine, so it'll probably be a while before any motor gets back into the truck while I clean things up. I mostly just want to make sure my conversion plans are realistic in terms of cost and effort. I enjoy the research.

I bring up OEM cars, 'cause you can buy entire Leafs for $6-8k. If the fabrication and hacking needs are onerous, it may wind up being more expensive in time and effort. That's what I'd like to figure out. I'm very much down for the well-trod territory. I definitely can't mate a random motor to some or other transmission, but I can certainly buy a kit and bolt things up...

It's smelling like the HyPer 9 is good motor based on price/spec, and going with a 9" or 11" cylindrical motor is well-trod territory. I guess I gotta research what's really involved in getting controllers to work well with an unknown vehicle...

That Torque Trends reduction box looks sweet. Looks like it would be great for a direct-drive application with a custom driveshaft to the rear. At $3k, though, it would be a hard sell vs the several cheap 3-5sp transmissions I could bolt up, and it doesn't seem like it'd be easy to mount to the input side of the transfer case.

Can anyone point me towards a resource for understanding torque, horsepower, and efficiency at various RPM as it relates to electric motors? I understand the difference between torque and power, but I'm uncertain about the "preference" of an electric motor. I always though it was best to run a motor in the "meat" of the torque, but I'm reading that electric motors are more efficient at higher RPM despite having less torque there. How do you know what motor speed to target vs vehicle speed? What are the tradeoffs for higher and lower?
 

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Discussion Starter #13 (Edited)
On a whim, I charted what some of these gears would look like with my janky gearing calculator, Gear Wars (and some Photoshopping):



Red is a typical Jeep/Bronco 5spd with a 4.11 final drive. The blue is direct-drive with a 2:1 torque reduction box. Green is direct-drive. The blue and green cover a "range" of a final drives from 3.00 to 6.50, all of which are readily available for a Ford 9" diff.

Targeting a 3300 rpm max continuous motor speed (which is what I've read the continuous maximum of the HyPer 9 is), it seems like there might be too much compromise. With a top speed of 60-75mph, I suspect 0-40 acceleration would be quite sluggish. A 50mph top speed might work, but it makes highway driving dicey.

It would be nice to lose the weight/complexity of the transmission, transfer case, and front gears, but it would be a bummer to have a car that was both sluggish off the line and low on top speed...all while losing 4WD.

Reduction box is $3-4k plus custom driveshaft. Tranny adapter is $1k.
 

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Reduction box is $3-4k plus custom driveshaft.
Yes, specialty items like the ev-TorqueBox are expensive. That's why the ideal is to buy used, and so let someone else take the hit of buying new and selling at a big loss when they change their mind; for instance, John has a nice motor with an ev-TorqueBox for you:
Huge 1/2 off sale must go; brand new Siemens motor bolted to brand new gear box.

If you are really lucky, the motor and gearbox would fit into the transmission tunnel, leaving underhood space for battery modules, but don't bet on that without detailed measurements.

Out of curiosity, where would the other $15k that I'm not accounting for be spent?
On stuff like an extra multi-thousand-dollar gearbox. ;)

But seriously, projects just almost always cost more (and take longer) than anticipated, and so the crack about doubling the budget. :)
 

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On a whim, I charted what some of these gears would look like with my janky gearing calculator, Gear Wars (and some Photoshopping)...
Was "Gear Wars" supposed to be a link? There's no target web address.

The chart is good... now, I suggest leaving off the right-hand half for readability (are you really going to go 80 mph in an EV-converted early Bronco?), extending the transmission gear lines up (to consider what you could do with a higher-speed motor), and maybe marking it up for specific cases (of motor and gearing) to be considered.

Targeting a 3300 rpm max continuous motor speed (which is what I've read the continuous maximum of the HyPer 9 is), it seems like there might be too much compromise. With a top speed of 60-75mph, I suspect 0-40 acceleration would be quite sluggish. A 50mph top speed might work, but it makes highway driving dicey.
Here we see why production EVs don't use <4000 rpm motors. The Chevrolet Spark EV was an oddball exception, running a large 105 kW and 443 Nm (327 lb-ft) motor with tall gearing (overall 3.17:1 initially, 3.87:1 later), but GM didn't continue that approach with the Bolt.

By the way, when I checked the Spark EV motor power Google showed me an ad, which says that the whole Spark EV motor is available for CAD $2849, new! Hilarious, given that there were nearly zero Spark EVs sold in Canada.

It would be nice to lose the weight/complexity of the transmission, transfer case, and front gears, but it would be a bummer to have a car that was both sluggish off the line and low on top speed...all while losing 4WD.
Ah, the importance of understanding what characteristics are important... ;)
 

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Discussion Starter #16 (Edited)
An $8k controller for a $3k motor. That's pretty wild. What does that get me beyond the $4300 HyPer 9 IS setup...? Seems slightly more powerful, with higher max rpm, but I'm not sure I understand where the spend is going.

I'm also not sure I'm ready to start sourcing EV components...but used does seem like the way to go. It's nice that you can get a lot off from retail, but a rather frightening return from resale...

Edit: Whoops...Gear Wars link fixed.
 

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That Torque Trends reduction box looks sweet. Looks like it would be great for a direct-drive application with a custom driveshaft to the rear.
Exactly what it's for, but the "direct drive" terminology makes no sense to me, with a transmission and final drive unit (with a reduction gear and differential) between the motor and axle shafts - there's nothing "direct" about that, it's just single-speed. ;)

... it doesn't seem like it'd be easy to mount to the input side of the transfer case.
No, it wouldn't, because it's not designed for that. It would be a good match with a divorced transfer case; there are lots of those, but they are much less common than "married" (attached to the transmission) transfer cases. You can even get kits to convert a common transfer case to divorced.

This does raise an issue with any configuration not using the original transmission (or similar), but keeping the transfer case: some custom-built shaft coupler and housing adapter would be needed to mate any motor output to the transfer case input. It's like the situation at the input to the transmission, but with no ready-made components available.
 

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What does that get me beyond the $4300 HyPer 9 IS setup...? Seems slightly more powerful, with higher max rpm, but I'm not sure I understand where the spend is going.
A fair question...
The rated power isn't much different between the HyPer9 and a typical modern EV motor (Spark, Leaf, VW, whatever). The difference is that with it's low operating voltage, the HyPer9 can only produce that power over a narrow range - say 3300 to 6000 rpm - while the production high-voltage setups do that over a broad range (2700 through 9700 rpm for a Leaf). That means that if you have a single-speed transmission, the production motor will out-perform the HyPer9 at most speeds.

(production EV motors such as the Leaf in their stock configuration with 360 V battery and suitable inverter have constant (current-limited) torque output up to a transition speed, just like the HyPer9, but then maintain constant power to nearly their rev limit, instead of starting to drop off only a couple thousand RPM later)
 

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Targeting a 3300 rpm max continuous motor speed (which is what I've read the continuous maximum of the HyPer 9 is)....
I'm puzzled by this. 3300 rpm is just where the HyPer9 reaches its maximum power region. If you gear the vehicle to never run the motor past this speed, you'll literally never get full power from it, and you'll typically have a small fraction of that available.

Why wouldn't you gear for 6000 rpm at the highest desired cruising speed, with the HyPer9? Production EVs are geared for nearly max motor rpm at max allowed speed.
 

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Discussion Starter #20
Interesting. Are there no aftermarket motors that take high voltage and therefore have a broader operating range, or am I just unaware of them (or are they crazy expensive)?

With battery costs dropping every time an EV crashes, seems like higher voltage battery packs will become more and more accessible...

My motor research is limited to like, what EV West publishes on some sale page...It's hard to find specs on this stuff, and I'm already pretty ignorant with regard to the numbers (and terminology, as you've noticed).

Coupling the motor to the rear diff via a reduction box and driveshaft is about as simple as it gets for driving and installation, but I wonder what happens to the cost in motor, batteries, and controllers to run in this configuration with ample acceleration and sustainable highway speeds...
 
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