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Tesla LDU drive shaft conversion

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32K views 66 replies 17 participants last post by  Roadstercycle  
#1 ·
Here everyone,
Thought I'd give you a project update as to what I've been working on ever since AEM bought my Mustang GT Tesla conversion. I decided to make an all wheel drive electric Ford Focus but got lost in Covid hell. So in the mean time I designed and built a new Tesla motor conversion for putting in old Mustangs and Camaro's that does not mean cutting up a classic car. So I developed a split Tesla motor with pressurized oiling, ability to run forward or reverse continuously and direct connect u joints or other types of power take off options. Here's a few picks. I have on the test bench right now playing with it. RPM red line should be about 5700 RPMs as with most V8 cars of yesteryear or yesterday. The motor and inverter are separate units now. Anyway enjoy a few pics. I'll now be hunting the donor car for the project. I'd really like a 1968 Plymouth Barracuda for this.

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#2 ·
This is a pretty novel approach. I think one of the turnoffs of the Tesla swap is that it must use cv shafts direct to hubs. While this does work when purchasing engineered shafts and hubs, I have seen some pretty dangerous conversions with welded axles and such.

I will be interested in following this. What did you plan to do for differential gears?

James
 
#3 ·
Hi Flashman, I am using a 2019, 5.0 Mustang 3:55 gears track pack differential. I've changed my coupling to a quick disconnect for being able to tow it to the track without sacrificing battery at the tracks where there's no charging available. Pretty much the not so local Irwindale race track In California. The donor is a 2008 Volkswagen Rabbit. Hopefully it will be as clean or cleaner than my 2007 Mustang GT Tesla swap. You can see that one on Youtube, I have the whole build there start to finish. Here's some pics of the new setup.

 
#4 · (Edited)
I am using a 2019, 5.0 Mustang 3:55 gears track pack differential.
...
The donor is a 2008 Volkswagen Rabbit.
Since you show the entire rear suspension and subframe from the Mustang, are you using that in the Rabbit body? That should work, although of course it means substantial structural changes and there's a five-inch track width difference to accommodate... wide rear fenders would presumably be in the plan.

By coincidence, the Ford Mustang independent rear suspension is of the same design (Integral Link) as the Tesla Model S/X independent rear suspension. Ford, Jaguar, BMW and Alfa Romeo all use the integral link design; BMW has been using it for three decades.

An alternative would be to just swap the entire Model 3 rear drive unit with subframe and suspension - no drivetrain customization needed, motor and gearbox tucked into the subframe, and a better track width match. Of course, then there would be no need for the split Model S drive unit.
 
#8 ·
Actually what does the Rabbit have to do with it? It's just a body I choose. I have 6 batteries in the engine compartment. My idea was with the motor directly attached to the Mustang diff I can get the perfect weight ratio and I can change the ring and pinion from 3.15 to 4.56, actually even higher but I won't be climbing any walls with it. Tesla is 3.14 to 1 if you want to compare. Can you change the rear ring and pinion on a Tesla on a whim? Not really. Zero EV makes I believe a 4.15 to 1 or something close to that for big tire Land rovers so there's no sense in bringing that up.
 
#10 ·
There's a real market for this. Right now, the only motor that is easily hooked up to a driveshaft or ICE transmission is the pricey aftermarket AC51/Hyper9 or the Nissan Leaf. The Tesla motor has more torque and a higher RPM than all of them...and now that I know half the Tesla motor is a detachable inverter...it makes packaging much easier since they can be separated!
 
#13 ·
Here everyone,
Thought I'd give you a project update as to what I've been working on ever since AEM bought my Mustang GT Tesla conversion. I decided to make an all wheel drive electric Ford Focus but got lost in Covid hell. So in the mean time I designed and built a new Tesla motor conversion for putting in old Mustangs and Camaro's that does not mean cutting up a classic car. So I developed a split Tesla motor with pressurized oiling, ability to run forward or reverse continuously and direct connect u joints or other types of power take off options. Here's a few picks. I have on the test bench right now playing with it. RPM red line should be about 5700 RPMs as with most V8 cars of yesteryear or yesterday. The motor and inverter are separate units now. Anyway enjoy a few pics. I'll now be hunting the donor car for the project. I'd really like a 1968 Plymouth Barracuda for this.

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Looks a little too compact for the HP.

What chain and sprockets (incl ratio) did you use to get from the motor to the driveshaft yoke?
 
#17 ·
That said, a 5000+ rpm driveshaft speed may be gearing it too tall for street use
The sample installation uses a Mustang final drive with a 3.55:1 ratio, which seems like a reasonable typical use. At 5700 RPM driveshaft speed, that's 1605 RPM axle speed. With the stock tire size of that car (315/30R19 for the GT350R track pack), that's 123 MPH or 198 km/h. That makes sense for a car that will see track use, and most variants of a 2019 Mustang can go much faster; however, a street-only car could use significantly shorter gearing for better acceleration. With only one ratio offered in the drive unit, the final drive ratio can be changed to suit the application; if the donor car were a track pack Mustang GT350 it would have had a 3.73:1, and even shorter ratios (such as 4.10:1) are available for that Ford "Super 8.8" final drive.
 
#18 ·
Here everyone,
Thought I'd give you a project update as to what I've been working on ever since AEM bought my Mustang GT Tesla conversion. I decided to make an all wheel drive electric Ford Focus but got lost in Covid hell. So in the mean time I designed and built a new Tesla motor conversion for putting in old Mustangs and Camaro's that does not mean cutting up a classic car. So I developed a split Tesla motor with pressurized oiling, ability to run forward or reverse continuously and direct connect u joints or other types of power take off options. Here's a few picks. I have on the test bench right now playing with it. RPM red line should be about 5700 RPMs as with most V8 cars of yesteryear or yesterday. The motor and inverter are separate units now. Anyway enjoy a few pics. I'll now be hunting the donor car for the project. I'd really like a 1968 Plymouth Barracuda for this.

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Hey Man,

This post immediately struck my eye. I have a 1964.5 (first ever!) mustang convertible that I have been looking to convert with my dad as a fun and challenging project for a while. The problem with looking for kits has been either they are too expensive or too boring (not enough power!), thats why your solution struck me, because I could use a tesla motor which packs the power and just sounds so cool. I am wondering if you would be willing to sell the U joint converter to us so we could use it in our build?

If so, please let me know the price, and maybe we could even pay you to consult us on the build if you would be open to that! thanks, Parker

P.S. I would have sent this as a private message, but I'm new and not able to yet :D
 
#27 ·
Great point and the 8000rpm speed at 9.1:1 would be about 879 wheel rpm and with a 28” wheel that would be 73mph, which would be around my primary cruising highway speed, perfect.

The motor max speed is a whole lot less important than the rpm at which field weakening begins. You don't want your cruise speed to be using FW or your efficiency will drop quite a bit, as will the steady-state power of the motor. LDU is a bit over 8krpm
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#25 ·
^^ Your post is very confusing.

The Tesla motor spins way too fast. It needs a gear reduction. That motor + reducer takes it to 3.12:1.

The yoke connects to the driveshaft and the driveshaft connects to the diff pinion input. That's not "1:1", it's a driveshaft. The diff has a 2.93:1 reduction to the axles.

There isn't a 1:1 gearcase anywhere.

You're also not going to exceed anything "momentarily". Top speed is governed. On the Bolt EV it's 93. Leaf is 89.5 mph. No reason to go faster in the USA.
 
#26 ·
Sorry I didn’t clarify, I want to add the Tesla motor to an existing ice car to make a hybrid.

So I would not just connect the yoke to the drive shaft and run it to a diff, that’s what I would do for an ev, not a hybrid. I need to put the e-motor inline with the ice run drive shaft so the e motor provides acceleration assist.
 
#30 ·
No, it's not readily supported. A transfer case in high range (direct) could be used, but that's a lot of hardware.

An alternative would be to use the whole Tesla transaxle with the available 4.5:1 gearing and a spool replacing the differential, feeding the transmission output to one side of the Tesla transaxle and taking the combined drive from the other side to the axle/final drive. This is a large pile of hardware, so it would only be suitable in a relatively large vehicle... and one that needs such a large motor in a hybrid configuration.
 
#31 ·
Wow, I have not logged in a bit. So here's some answers. The output is a 3.12 ratio and the diff is a 3.55 so we end up with an 11:07 final drive, great for quick 1/8 mile and rally cross but not high speed. The car was built to test the feasibility of doing this with drive shaft setups in older Mustang and Camaro builds. So far so good but I'm being driven crazy by the gearbox oil pump whine. Any thoughts on that would be appreciated for sure. I'm using a gear pump which are really noisy. I just put 2 new videos up on YouTube with the Tesla under glass Rabbit build and my latest Mustang build with the Model 3 motor. Here's the links.


 
#32 ·
Dug late in to this one & not sure if there's a newer post with updated info, but I really like this as a possible option for my '68 camaro built... I have a Roadster Shop chassis & a Read Deal Steel body, so basically building a Camaro from scratch with a full frame and very interested in this way of utilizing the Tesla setup... If there's another post I missed, I apologize. I'll keep digging! :)
 
#33 ·
I'm guessing few here know what a Roadster Shop chassis is and people are too busy to go research information you already have.

For starters...

Does it have IRS? What's the inner spacing of the frame rails? What's the track width? Are you willing to flare or tub the body? "the Tesla setup"...which one? What do you want out of the car by doing this?

Take a look @428RC's Corvette thread to see what kind of PITA it might be to squeeze a Tesla LDU (one of many "Tesla setups") into a custom frame.

Also pick up a copy of May 2022 Hot Rod magazine to see what GM is about to launch, which might work better for your application than a Tesla DU. They electrify a 57 Chevy with the GM factory team involved who want to launch a "crate motor"
 
#34 ·
The Roadster Shop SPEC chassis (likely the one already purchased) has a beam rear axle with parallel lower and angled upper control arms. Although no single detail is the same as a the stock 1968 Camaro, it is designed to use a stock body and stock-style (or more likely more modern equivalents) powertrain (engine and transmission). The problem with using it for a conversion will be finding somewhere to put the battery.

This thread is about adapting a Tesla motor to be placed longitudinally, driving a remote axle, which could work with the stock Camaro layout. The obvious alternative is to use an entire EV (Tesla or otherwise) drive unit at the rear axle, with an independent suspension instead of the beam axle. That would leave the entire engine compartment for battery, but of course mechanically it's bigger project (due to the required IRS), and it would require body floor modifications (which the RS chassis carefully avoids). The frame rails of the custom chassis are widely spaced (because of the design for a beam axle which is good for fitting in the width of a drive unit, but will be in the way of most IRS.

The Roadster Shop Fast Track chassis is available with IRS. The IRS design (which likely uses C7 Corvette parts) has relatively short arms and widely spaced frame rails (although not as wide as with the beam axle), so it might be a reasonable basis for build with a complete EV drive unit in the rear. The bolted-in rear subframe or crossmembers would need to greatly modified, or completely replaced.
 
#35 ·
You're correct, Brian... I would be interested in utilizing this as a way to place the motor unit in a traditional motor placement (or maybe where the Transmission would be- I have to cut the body tunnel for a T56 Magnum if I went a fossil route anyway) & run a full driveshaft. Building out the batteries around it in the engine compartment, then in place of the fuel tank. Just an interesting option. No desire to chop of the RS chassis... more mentioned because it would be great for torque management vs. just a unibody with subframe connectors.
 
#41 ·
Hi Breeze612, My design is using the primary and secondary Tesla gear reduction and then comes out to use a Dana yoke for various u-joint setups. Testing so far has been quite promising and I don't see really any issues except a noisey oil pump that is splashing the internal Tesla gears. I have moved to a Model 3 gear pump which is much much quieter. I have to design a tank so that the gear oil from the gears spinning will separate the air that gets in the oil. That makes the pump a little louder but still holds 30 PSI which is about perfect. I am going to the Irwindale drag strip drag strip tomorrow to personally to talk to tech about running both the Musktang M3 powered and the VW Rabbit LDU powered split motor. If all goes well with tech then I'm looking at next week for maybe some 1/8 mile times with the "Watt's Up Doc" VW Rabbit.
 
#46 ·
If you are looking for good oil pump options for future iterations, Mezieres (disclosure: family) makes a few pumps that would be a good potential fit <https://www.meziereindustrial.com/products/displacementpumps/>. The WP702 is a two stage pump (scavenge and pressure all in the same pump) that would make a pretty trick dry sump system pump. The WP701 is a single stage version. The have been used with a lot of success in ev applications.
 
#43 ·
Remy, The article was from 2020 very outdated fro what is really going on. I talked to the Revolt business owner (my grapevine) and EV West is not even part of the project, that's another story all together. Give Revolt a call and get the up to date scoop, you'll be amazed as to what is really happening now. Revolt does have those motor setups coming along but like I said I don't think $35,000 will even get a base one at this point.