I’m finally making some progress on the adapter plate. I have machined a mockup out of MDF. Now I have to verify the pattern before I start machining it out of aluminum. Things have been going kind of slow since I only get down to the shop once a week and I’ve been spending quite a bit of time getting the mill running well.
I drew up a design for the adapter plate in SolidWorks. I think it is pretty much done. I will have to verify the thickness before I cut it out. I will put the coupler on the motor and measure how much it is sticking out from the face of the motor. I may make the tapered hole in the back of the coupler a little deeper to allow the bushing to seat in a little further to get the whole assembly a 1/4″ or so shorter.
This was my first foray into using SolidWorks and I have to say that it’s a pleasure to use. If only it was a Mac OS application and not so ridiculously expensive.
In the past I have used Rhino for things like but it makes it much more difficult to go back and change things. With this drawing could modify things like the thickness of the ribs by just changing one number.
I finally decided that the way to go was to make a coupler that accepts a QD bushing and bolts to the back of the flywheel.
I drew the part up a couple of times in Rhino until I got it the way I wanted and then decided to draw it up in the emachineshop.com software to see how much it would cost to have them fabricate it.
I finally bit the bullet and put down a deposit for a Z2k controller from Cafe Electric.
The controller is capable of pulling 1900 amps out of the batteries at 200 volts. This is a more than twice what the T-Rex controller I had in there could do.
The main thing that pushed me to switch to the Zilla is the amount of configuration you can do with them. The T-Rex was a nice controller but it basically had one adjustment which was the max current (well, it also had a rev limit setting). The Zilla can also return some data about the current operating conditions over the RS232 link.
I’m hoping to have a small linux based computer (probably a Nokia N770) that will grab data from the Zilla and from the battery regulators (probably Manzanita Micro Mk3 Regs). The regulators will be able to return the voltage of the individual batteries. The computer could also be set up to modify the settings for the Zilla (like the current limit).
I will probably have the current limit dialed down most of the time since I think maximum limit will break stuff pretty quickly.
Now that the transmission modifications are mostly sorted out I have to get on to figuring out how to couple the motor to the transmission.
In my old setup, there was a coupler attached with set screws and a key to the motor shaft. This seems to have been ok but the general consensus seems to be that this will fail under higher power setups. Since I plan to hopefully make my car a little more peppy, this is a little of a worry so I am hoping to switch to a more durable taperlock setup.
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The new transmission came a while ago. The differential that cam with the transmission had been welded by the previous owner so I needed to find a new differential. I decided that since I was replacing the diff it would be nice to have a limited slip in there. There are always a few JDM LSDs on ebay so it wasn’t hard to find one.
I was pretty sure that some modifications would be required to fit the differential and upon opening the case and attempting to fit the diff. it looked like they wouldn’t be too extensive.
There was some webbing in both halves of the case that needed to be ground down so that the differential wouldn’t rub. I also had to replace the bearing from the bell housing side of the differential with one from a 2000 integra type-r (part number 91005-P80-E31). This bearing is a little taller which stops the speedometer gear on the differential from rubbing on the case.
After the modifications the diff appears to fit fine. Now I just have to order the shims, the gap is a little larger than normal so I may have to stack two shims but I don’t see why this would be a problem.
Well, it looks like things are calming down for me so I’m hopefully getting ready to get the EV back on the road.
The main change that I am planning on making to the EV is that I will be replacing the transmission with a b-series transmission from a ‘92 Acura Integra. This will make it possible for me to find a much stronger clutch and possible a limited slip differential. The ‘87 transmission was just too old and there aren’t many cars with that transmission making a lot of power so the clutch offerings for it were pretty slim. I probably could have gotten a multi thousand dollar clutch for it if I wanted but with the B series trannsmission I can get a pretty stout clutch for much less.
I’m also going to be rearranging everything under the hood. The controller was towards the middle of the engine bay before and I have decided that I would rather have it as far back as possible to keep it away from the weather. I’m also going to try to finally make the wiring nice and neat since it was a bit of a rat’s nest before.
So, now I have wait for the transmission to arrive, then I have to get a new adapter plate made to attach the motor and get some motor/transmission mounts to put the new transmission in the car. Conveniently there are a few off the shelf motor mounts for that transmission/engine combo since people have been sticking the more powerful b-series motors in that car for quite a while.
So, the CRX has been off the road for more than 2 years (since before my son was born and we renovated and moved into a new house). I originally stopped driving it because the water pump for the controller had died. Then I decided that I wanted to make some improvements and generally get it more finished so I took it apart a while ago and haven’t gotten around to working on it since. Well, hopefully I will start getting some work done on it and get it on the road before the end of the summer…
