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Kudos ToyXCAB89. I did something very similar with a BMW conversion. Went a slightly different approach, and rather than drill out the crankshaft flange to slip over the motor shaft (which I think is a great idea), instead left a "stub" off of it that turned-down to the same diameter of the motor shaft, and then used a shaft coupler. The attached picture sort of shows it. In the end, it worked very well. Took some time to get the balancing right though. When you want to use a clutch (which in many cases, I do agree is still a good idea), and you're running out of options for an off-the-shelf adapter/coupler, it is pretty good approach. You just need a good machinist to get that crankshaft end done right.
 

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Cejota3,
I think that this was one of my first thoughts.
How did you do it? How is it attached?
Not sure if you can tell from the pic I posted, but basically I've got a "coupler" that seems to be like that one your holding in that picture. A "double clamp", "keyed" type. I could track down the model # and where I bought it on another day if someone really needs to know.
The backside of the crankshaft flange/stub I used I had lathed down to the same diameter as the electric motor shaft (basically the last main bearing portion of the crankshaft) and then had it "keyed" as well. I don't have any other good pictures of it at the moment.
I found that double-clamping coupler really helped keep it steady, because as I said in the first post, I had some "balancing challenges" at first (a whole other story) that kept on loosening the other couplers I tried, for example those that just had a single set screw.
I also had "z-axis" issues, basically the pressing force when the clutch was engaged (think pressing the clutch pedal) creates a lot of force pressing against that coupler towards the motor. So inside that coupler, between the motor shaft and the stub shaft off of my coupler, I had to add some spacers. Looking at your pictures, it seems like that might be something you have to deal with also, but kind of tough to tell for sure.
 

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Not sure if you can tell from the pic I posted, but basically I've got a "coupler" that seems to be like that one your holding in that picture. A "double clamp", "keyed" type. I could track down the model # and where I bought it on another day if someone really needs to know.
The backside of the crankshaft flange/stub I used I had lathed down to the same diameter as the electric motor shaft (basically the last main bearing portion of the crankshaft) and then had it "keyed" as well. I don't have any other good pictures of it at the moment.
I found that double-clamping coupler really helped keep it steady, because as I said in the first post, I had some "balancing challenges" at first (a whole other story) that kept on loosening the other couplers I tried, for example those that just had a single set screw.
I also had "z-axis" issues, basically the pressing force when the clutch was engaged (think pressing the clutch pedal) creates a lot of force pressing against that coupler towards the motor. So inside that coupler, between the motor shaft and the stub shaft off of my coupler, I had to add some spacers. Looking at your pictures, it seems like that might be something you have to deal with also, but kind of tough to tell for sure.
Oh, I guess I'm missing an important part. I also "sliced" off the back of the engine block that the crankshaft came from, had that milled flat, and then devised a way to have that mount to my motor, and then of course, that "adapter plate" naturally connected perfectly to the tranny bell housing (because it used to be the back of the engine that would connect to it). Here is a picture that shows it mocked-up a bit before I had it all dialed it. It's not shown in this picture, but the crankshaft "adapter" would then just sit where it normally would. Got rid of the RMS (real main seal) because you obviously no longer need that.
(I'm actually on vacation at the moment, without access to a lot of the pictures that would better show all of this!)
 

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