Ben is a little behind in the video’s. I’ll post the video links here as more become available showing the work involved. You can also keep track of it in his youtube channel and subscribe etc.. what ever you choose.

As for now here is a little sneak peak of the progress on the front drive unit. Its only supported by the side mounts. More work will be done for the front/back roll.

 

So this is the car Ben has been posting about.

Awesome to see.

Was sad when the other thread went dead.

 

Yes , this is my car Ben at Hochman Fabrication and Speed is making the drive unit mounting subframes. The other thread your referring to is someone else’s car who was using Warp 9 DC motor mounted to the Evo drivetrain . His build thread is what sparked my interest in the EV conversion.

Here is a pic of the rear subframe off the car . It got additional reinforcement welded in. It will also get powder coated soon when the front is done.

 

So the above photo is the finished product before our plan to get it powered coated . Here is the video clip on the fab work involved for that rear piece .

 

A friend of mine made a video to better understand the BMS wiring for EV conversions. I highly recommend watching if your interested in learning more about what is involved .

The BMS (Battery Management System) in short explanation monitors the battery cells, balances them and ensures they are running too low or high in voltage , not overheating etc..

 

are you still selling the shell?

 

No, I decided to keep it and finish the project when I can.

It’s currently in dormant stage as we wait for our house to be completed in a couple months . Then once we move in and get settled , I will slowly start again .

 

Finally got in my new place . Although I don’t have a lot of time to work on the car , what little tile I had I did a lot of observations of the setup I have and better solutions .

Starting with the front drive unit setup , I was under the impression it could not fit the forward facing orientation . But that is not entirely correct . It can fit if we clock it/tilt . The only issue is clearing the bracket holding the ABS module , which can easily be replaced with something custom .


The challenge with the front bay is the frame railed on each side are not nice flat square tubing . There are a lot of contours and minimal desirable surface areas to take advantage of .

FirstI centered the front drive unit to get close approximation of where it would sit . In the process i decided to delete the “jack shaft” . I heard Tesla owners complain having vibration issues , so why not remove it completely and center it all to equal axles. I cut and trimmed the bracket in the case holding the oem jack shaft so it can clear the cv case.





Here is the bracket I made that bolts to the drive unit . Added a bunch of gussets so it’s structurally strong .



Next up was the bottom bracket that bolts on to the frame rail. This is before the bolt holes .



I used two rubber mounts sandwiched in between .




I also made a bracket/arm for the driver side . The passenger side bracket does grunt of the work, the purpose of the driver side is just to hold it/titer .

 

Now it’s time to fix the rear . The drive unit was not centered , so if I’m not mistaken unequal axles result in torque steer like issues during acceleration .

First step, I removed the “subframe” to look things over and determine if I can modify it so it’s not a total waste . Regretfully I won’t be able to use it if I want the drive unit to fit centered . Also I noticed it’s kind of crooked .






The factory control arm camber bolt box would need to be pulled out toward the wheels for it to fit . Here is the rear drive unit centered and higher ground clearance . I will need to make a new subframe to run shorter lower control arms . I really don’t want to make custom control arms and sadly STM is out of stock of theirs . So I’m in the hunt for STM control arms I can modify . I will need to be about 2.5 inches shorter than oem .


If anyone has STM lower control arms they want to sell let me know .

 

Thank Jeebus this is still happening!

 

Great build ! Keep it up

 

That is a strange assumption. Torque applied to an axle is dependent on the axle radius. Remember radius crosses Force. http://hyperphysics.phy-astr.gsu.edu/hbase/tord.html

Most vehicles have unequal axle lengths. I am not sure why you came to this conclusion.

 

Here is a nice explanation of how unequal cv shafts cause torque steer.



More importantly for me , Tesla designed and incorporated the Jackshaft on their front drive units to create an “equal length” cv , as the front drive unit is not centered . I assume their engineers are right .

 

Yes I agree with his solution specifically at 7:05-9:30 of that video.
1. Ford and GM both created solutions to torque steer that were for their existing FWD cars.
2. Those FWD cars were already using front axles with one intermediate shaft.
3. Minimizing scrub radius and adjusting the LSD to counter the torque steer were the biggest effects in reducing torque steer.

Tesla is just using a existing solution that was previously created for FWD cars. The Tesla Jackshaft is an intermediate shaft. Seems like a good way to start by using one of those as a quick way for a machine shop to make you a custom length one for this application.

Anyways, the Evo has unequal front axles so thats why I was wondering why you were trying to center the drive unit. It seems like way forward would be to mount the drive units where the placement is convienient. Some braces can be mounted off of numerous mounting positions in the engine bay. Off the top of my head the front subframe would be a good candidate. These tubular braces would be where you can correct the axle angles and add intermediate shafts if you were worried about the torque transfer through the axle.

Revo knuckle solution to torque steer explained by Ford.

Handling guide with guidelines to desired AWD scrub radius.
https://motoiq.com/the-ultimate-hand...n-and-scrub/4/

Intro to Scrub Radius

 

@deylag

Honestly I’m not sure what you’re trying to get to . Pretty much all those clips and information further validate that having unequal cv shafts cause torque steer from the different angles created by the unequal shafts. . Ford and GM created their own band aid solutions to help , as it is not possible for the drive train to be installed in such to run equal length cv shafts . But they used combinations of the knuckle system and special adjustments to the lsd. For me it’s way easier to solve the issue by centering it than add more band aids.

For the record , the Evo front cv shafts lengths only have a difference of about 2.5” . (measuring between the cv boots) Also if im not mistaken the rear are pretty equal , which might help .


I deleted the Jackshaft from the front drive unit , so the center point changed . This change is beneficial for me as it brought the motor closer to the frame rail for the mounting bracket design I made . Yes I could have done things differently and created some tubular design connecting to the subframe , but that complicated things and in some ways may have taken up more space in the engine bay. This orientation I have set also opened up a lot more space for other components like batteries , conjunction box , etc…

As for the rear , the drive unit centered keeps in line to how the Evo was with the rear diff and how the Tesla was originally . Perhaps the Evo rear diff having “equal” or close to equal length cv shafts helped a lot to its awd platform . And fwd probably suffer more because they don’t have an acceleration source from the rear wheels .

One other thing to keep in mind, other than space limitation there are also challenges of angling it correctly to both axis. .

Anyways, I don’t want to create a huge debate over this topic.