DIY Electric Car Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
Hi all.
I am all new to the EV conversion world. I know all my questions could be answered by going through the enormous wealth of information on this site, but I thought I would introduce my plans here, and embed some questions that knowledgable people could answer if the fell like it.
My plan is to convert my Volvo 3314…Not many people know what that is, but it is a small military truck, the size of a Series Landrover. It has the engine placed between the seats, with a standard Volvo Amazon gearbox behind it, and a transfer case beside it.
Since I do not have the know how to put together a complete package, I am considering getting a conversion kit without adapters etc. As it looks, that will set me back 15k$ All included which is a bit steep, considering value of finished product.
I guess what I want to ask, is if there is a tool or guide, to put together a working package myself? (Motor, Controller, batteries, charger, etc).
Then there is the mechanical part of the build. The easiest way as far as I can tell, is to retain gearbox and clutch, and drive as normal. I am however trying to calculate if it is possible to connect the motor without the gearbox. This would probably require a reduction gearbox, which I would have calculate. The maximum speed will be 60mph, so should be possible with one gear.
Another option that i have seen used, is using a motor unit with built in diff, turn it 90degrees, and drive one axle from each drive shaft flange.
There are of course many other considerations at the current stage, but should be quite a straight forward build, as the vehicle is from 1963. Looking forward to read about other builds in here.
Tire Wheel Car Automotive parking light Sky
 

·
Registered
Joined
·
8,175 Posts
Interesting project. :)
The closest that I have seen to this in this forum is
Planning 1975 Volvo c304 electric expedition camper
The C304 is the 6X6 variant of the C303, which is the bigger and heavier successor to the Laplander L3314. The L3314 is a bit more conventional, as it has variants of common Dana 44 axles. Much of the C304 discussion is related to a possible hybrid system or specific to the 6X6 configuration, so it won't be applicable to this project.

Mechanically, despite the forward-control body layout, this is like many other 4X4 conversion projects.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #5 ·
Thank you for your input. I will check out the landcruiser project and other 4x4 projects in here. If I am do ditch the transmission, I will need some form of reduction, then onto the transfer case. I have not made the calculations yet, but I suppose it would be somerhing to simulate maybe something between 2nd and third on the M40 transmission. But the reduction gears I can find are around 4000$, so might just keep my first build simple, and leave the transmission in.
I am still fascinated by the idea of turning a motor/diff unit 90 degrees and thereby ditching both transmission and transfer case. Some change in the motor unit would have to be done to match revs to desired wheel speed.
 

·
Registered
Joined
·
8,175 Posts
I am still fascinated by the idea of turning a motor/diff unit 90 degrees and thereby ditching both transmission and transfer case. Some change in the motor unit would have to be done to match revs to desired wheel speed.
Yes, I was working on that...
The rotated transverse production EV unit approach has, in general, four issues:
  1. the gearing will be wrong, as the outputs will be geared down too much to also go through the axle reductions
    • for a Tesla large drive unit (only), Zero EV and others offer a gear ratio change kit
    • the axles are apparently Salisbury units based on the Dana 44 design, so replacement ring-and-pinion sets with different ratios should be available... maybe the tallest ratio would work for the large tires and limited top speed of the vehicle, even with stock drive unit gearing?
  2. splitting drive to front and rear:
    • if the transfer case is used, the EV drive unit differential must be locked to use only a single output, and the combined offset from the centreline of drive unit and transfer case will be too much
    • if the transfer case is not used, the EV drive unit differential will provide inter-axle differentiation (good, it give you full-time AWD) but no way to lock that when required off-road
      • a spool would prevent on-road driving, unless a disconnect of some sort were added for one axle
  3. the EV drive unit axle outputs will be inline, and while the shaft to the front is essentially always offset to one side, the shaft to the rear is often on centre, so one shaft or the other won't line up with the drive unit
    • the L3314 looks like it might have both front and rear shafts offset (to the passenger/right side), in line with each other, and if so then there's no problem :)
  4. the EV drive unit would need to be rotated in the way which puts the output off to the correct side, which may require it to run in reverse all of the time
    • this may not be an issue, depending on drive unit
    • again, Zero EV and others offer an oil pump conversion to handle the reversed rotation
    • any drive unit which mounts the motor ahead of the axle line (e.g. Nissan Leaf) when turned to put the outputs on the right-hand side (as required by the L3314) would rotate the output shafts counter-clockwise when viewed from the rear, which should be correct for most vehicles :)
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #8 ·
Thanks Brian.

A lot of valuable info. The one in the Jalopnik article is exactly the same as mine. The “Feltvogn” (Fieldwagon) was the Norwegian model. The original Swedish version was nicknamed “Valp”(Puppy).
I suppose someting like the Leaf unit would be a good fit, as the Tesla units have way too much power for my use.
It will be used as a summerhouse run about. and not seeing much offroad action, besides backing the boat trailer across the beach. 60 mile range would do.
 

·
Registered
Joined
·
11 Posts
Interesting project to follow.
Good luck with the Valpen.
Why not contact Isak at Resolve?
Perhaps this build can give you a few tips as well:
 

·
Registered
Joined
·
8,175 Posts
I suppose someting like the Leaf unit would be a good fit, as the Tesla units have way too much power for my use.
Lots of peak power isn't a problem - you don't have to use it. ;) But yes, the Leaf seems like a more obvious fit. Also, it's more practical to detach a Leaf motor from its transaxle than it is to separate a Tesla motor from its transaxle, due to the way the housings and shafts are designed, in case you want to use the motor with the original transmission or other reduction gearbox, rather than the stock transaxle.

It will be used as a summerhouse run about. and not seeing much offroad action, besides backing the boat trailer across the beach. 60 mile range would do.
Moderate expectations are good!
Keeping a 4WD configuration, with the availability of either a locked centre differential or some equivalent, would certainly be desirable on the beach.
 

·
Registered
Joined
·
4 Posts
Hi all.
I am all new to the EV conversion world. I know all my questions could be answered by going through the enormous wealth of information on this site, but I thought I would introduce my plans here, and embed some questions that knowledgable people could answer if the fell like it.
My plan is to convert my Volvo 3314…Not many people know what that is, but it is a small military truck, the size of a Series Landrover. It has the engine placed between the seats, with a standard Volvo Amazon gearbox behind it, and a transfer case beside it.
Since I do not have the know how to put together a complete package, I am considering getting a conversion kit without adapters etc. As it looks, that will set me back 15k$ All included which is a bit steep, considering value of finished product.
I guess what I want to ask, is if there is a tool or guide, to put together a working package myself? (Motor, Controller, batteries, charger, etc).
Then there is the mechanical part of the build. The easiest way as far as I can tell, is to retain gearbox and clutch, and drive as normal. I am however trying to calculate if it is possible to connect the motor without the gearbox. This would probably require a reduction gearbox, which I would have calculate. The maximum speed will be 60mph, so should be possible with one gear.
Another option that i have seen used, is using a motor unit with built in diff, turn it 90degrees, and drive one axle from each drive shaft flange.
There are of course many other considerations at the current stage, but should be quite a straight forward build, as the vehicle is from 1963. Looking forward to read about other builds in here. View attachment 123614
Interesting project. Check out Zack Nelson. He’s converting a 4wd Hummer. Similar issues I imagine.
Good luck!
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #13 ·
Just had a chat with a guy building a Landrover EV with a Leaf unit mounted sideways, and using the standard diff ratio. He recons that it will me able to top out at around 50mph (80kmh). Whereas that may be enough to keep up on the highway, it means running motor at max rpm the whole time. Like if you were driving the Leaf flat out. I don’t know what that does to the efficiency of the engine, and the longevity of moving parts. I would have aimed for a theoretical top speed of maybe 70 or 80 mph, and then driven it at 50. A bit below max revs. Unfortunately the only gear set for reduction I can find, is for the Tesla LDU. None for Leaf of Tesla 3 units.
 

·
Registered
Joined
·
8,175 Posts
Just had a chat with a guy building a Landrover EV with a Leaf unit mounted sideways, and using the standard diff ratio. He recons that it will me able to top out at around 50mph (80kmh).
I'm surprised it's that high a speed, but if you have the tire size, axle ratio, and Leaf specs you can work this out exactly.

The tire size that I found in the first specs that I found for the L3314 was 285/85R16... that's big, is it correct?

Do you know the axle ratio? The Salisbury 4HA axle is extremely common in British cars of the era so there are lots of parts and a range of gearing choices; the 4HS is just the steering version and presumably fits the same differential and gears. One source lists 2.88, 3.07, 3.27, 3.31, 3.54, 3.58, 3.77, 4.09, and 4.55; the L3314 would presumably have a short (high number) ratio to suit the large tires and expected low speed, but using a drive unit with too much internal reduction gearing would call for the opposite extreme in axle gearing.

A Jaguar forum discussion suggested that the later 4HA axles are so close to a Dana 44 that ring and pinion gears can be interchanged, so there is a wide variety of choice... but early 4HA axles might be a problem. I'm guessing that 1966 is "late" on this time scale.

I don’t know what that does to the efficiency of the engine, and the longevity of moving parts. I would have aimed for a theoretical top speed of maybe 70 or 80 mph, and then driven it at 50. A bit below max revs. Unfortunately the only gear set for reduction I can find, is for the Tesla LDU. None for Leaf of Tesla 3 units.
Motor efficiency drops off at high speed and light load, which is what you would have on the highway in this case. I agree with the selection approach, and that planning for ordinary highway travel to be at the drive unit's maximum speed would be undesirable.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #15 ·
The number i can find for the diff reduction is 5:38, whatever that equates to. Rear diff has LSD. I know replacements are very hard to come by, so I assume can’t just interchange anything standard. I will try the 3314 FB group and see what I can find out.
Another option would be to adapt the Leaf engine to the transfer case. That would have the opposite effect, in that the 4th gear on the transmission is about 1:1, so you would essentially be starting and running in fourth. That would mean that instead of operating at the highest possible revs, you would be running in the bottom 3rd of the rev range. And loose a lot of torque i suppose.
 

·
Registered
Joined
·
8,175 Posts
The number i can find for the diff reduction is 5:38, whatever that equates to.
Wow, 5.38:1 (which is presumably what that was supposed to be) is short, but that makes sense given the large tires and low speed.

The top speed of a Nissan Leaf depends slightly on year, but is about 90 MPH or 145 km/h. With a base tire size of 205/55R16, and about 838 revolutions per mile for that size, that top speed corresponds to about 1260 RPM at the wheel or axle. A Leaf motor top speed of about 10,000 RPM and about 8:1 gearing (in the stock Leaf transaxle) gives the same axle speed.

1260 RPM out of the complete Leaf drive unit divided by 5.38 by the L3314 axle would result in only 234 RPM at the tires, which with 235/85R16 tires (655 revolutions/mile) would result in a top speed of 0.36 miles per minute or 21 MPH. That seems more likely to me than the 50 MPH mentioned earlier.

The relatively common 3.07:1 axle gearing would result in a 38 MPH top speed... still not nearly enough. Unless I have made a calculation error, it seems unlikely that the complete Leaf drive unit's output speed could be workable with any variation of the L3314 axles.

Rear diff has LSD. I know replacements are very hard to come by, so I assume can’t just interchange anything standard. I will try the 3314 FB group and see what I can find out.
Complete axle assemblies may be uncommon, and the pinion and ring gears of that ratio would be rare, but it looks like lots of Salisbury and Dana parts should be compatible. Definitely check out L3314 enthusiast groups for details, if any chosen motor configuration would be improved by different gearing.

Another option would be to adapt the Leaf engine to the transfer case. That would have the opposite effect, in that the 4th gear on the transmission is about 1:1, so you would essentially be starting and running in fourth. That would mean that instead of operating at the highest possible revs, you would be running in the bottom 3rd of the rev range. And loose a lot of torque i suppose.
Yes, using the motor alone is another option, and yes, it would likely need some additional reduction gearing (but not the roughly 8:1 of the Leaf transaxle). Reduction gearing divides speed and multiplies torque, so the torque to the wheels would likely be insufficient. There are reduction gearboxes available, but none are an inexpensive and trivial fit.
 

·
Registered
Joined
·
8,175 Posts
I would have aimed for a theoretical top speed of maybe 70 or 80 mph, and then driven it at 50.
Going back to basics, with 235/85R16 tires 75 MPH would be 819 RPM. With 5.38:1 axle gearing, that means 4400 RPM shaft speed to the axle. To match that to 10,000 RPM at the motor would require an additional reduction gearing stage of 2.3:1.

That's about what common transfer cases do in low range, but they're not likely compatible with a 10,000 RPM input, and part-time transfer cases are often not usable in low range while in 2WD.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #18 ·
Yes. 23mph is what I calculated using 1:5.38, 1:8.1, 34” tires, and 10000rpm.

A 1:2 reduction gear, then tranfer case reduction 1.35, then diff 5.38 would probably give me the best result. But reduction gearbox is around 4000$ and a special adapter needs to be fabricated. And I would not get rid of the leaky and noisy transfer case.
 

·
Registered
1996 Toyota Land Cruiser
Joined
·
580 Posts
I was looking around for reduction gearboxes to use for this same problem. I was going to try and find a 2:1 boat reduction box, which are quite common and cheap. They are not rated for the RPMs nor probably the torque. But maybe there is something there. I settled on a Northwest Fab Blackbox reduction unit which you could probably use with some custom work on your Volvo: Black Box Underdrives It is rated for the torque, but maybe not the RPM. I plan to cool mine well. Also driving in Hi/Hi for light duty stuff around city streets might be ok. Won't know til I know.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #20 ·
After some research and previous input from members here, the right way to go for me is the mid-mounted Motor turned 90 degrees, and using the diff from the donor car. The builds I have seen using this method, have used the Tesla Large Drive Unit, and there is a reduction gear available to reduce diff to 1:4,5. This however is also a very expensive build.
So far I have not been able to find a reduction gear set for the Leaf or the Tesla 3 drive units. But there are some options here. There is a UK company currently developing a setup with the Tesla 3 Unit, where the reduction gear will be available to buy at some point. The other option is to get a gear reduction made for the Leaf unit. I have been in contact with Quaife regarding having a set made. They are happy to do this, and will quote me a price pr set, when ordering 10-20 or 30 sets. They will also need a unit sent to them for the R&D of the gears. Going by the price of the gear set of the Tesla LDU, it would probably be in the region of 2500$ per set. If a group buy, or in indication of how many people would be interested in such a gear reduction could be found, it might be a viable option.
But this is where my lack of knowledge and understanding of EVs starts. The Tesla components, and aftermarket add ons are more expensive. Battery packs well above 10K for a pack removed from a car, and control units, cooling system and so on, seem more expensive and complicated. But do I need to use a full pack for a Tesla unit, if I don’t need the range and power? As far as I can tell, the max rpm will also drop if using a lower voltage, and this has to be figured into the gear calculation. And how low a voltage would the Tesla unit accept? Would I even have to cool it, if only used in a low power configuration?
The leaf option has ample power for my project, but since it is a weaker unit than the Tesla, reducing voltage to that unit would also mean reducing power and rpm?
Thankful for further input to my understanding of this kind of project.
 
1 - 20 of 20 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