Tesla Drive Unit Photo Fitting
The biggest unknowns about using a Tesla drive unit is how it will fit and how it will attach to the car. Since I am a photographer and I know how to use photoshop I made a photographic fitting of the Tesla small rear drive unit to my car. First, I took some pictures of the bottom of my car directly below the differential. I then made some measurements so I could scale the photographs. The distance from the end of the axle carrier to the side of the spare tire well is 21”. The Tesla small rear drive unit is 22” between the mounting points. So, it seems there is room to fit the Tesla drive unit. But the most important alignment is that the center of the drive section must be at the center of the output shafts. I grabbed a screen capture of a Tesla small rear drive unit and brought that image into photoshop and embedded it in the image of the bottom of car. I adjusted the size of the Tesla unit so it matched the scale of the photo. From this exercise the Tesla drive unit will fit with the drive section aligned to the output shafts. Toward the front of the car a simple mount can be used to bolt the Tesla drive unit to the axle carrier once the differential is removed. But the image shown below indicates that the other end of the Tesla drive unit mounting will have to be inside the spare tire wheel well. That will actually work out well as there are frame rails on each side of the spare tire well to tie a support structure for the Tesla drive unit. The mount that is on the left side of the motor in the photo can be changed to also tie into the frame rails. My Brusa battery pack charger is the only thing in the spare tire well and that can be located to somewhere else in the trunk because some of the batteries in the trunk will most likely be moved to the engine compartment. Other components that might have to move to the trunk are the DC/DC converter and the primary bus connection. The design of the car currently is engine compartment centric. That will all have to move to the trunk because the drive unit will be in rear of the car. The water cooling required for the Tesla unit will be another complication. The reservoirs/ pumps and cooling fan/radiator are in the front of the car. I will have to determine if pumping coolant from the front of the car to the back makes sense. A quick calculation of weight indicates one or two batteries will need to reside in the trunk. The other three will go in the engine compartment in a new battery box that will have to be designed to be weatherproof. The placement of the batteries will depend on the weight distribution once the Siemens motor, 5-speed transmission, driveshaft and rear differential are removed and the Tesla drive unit installed.
