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Discussion Starter #122
Moootor mounts! I've got the right side mount fabbed and tacked, and now I'm on to the rear and left.

I wanted to use the Nissan mounts, but the Honda subframe spars blocked them from fitting...I would either need to cut/weld the spars, or just use a simpler mount. I'm gonna give these a whirl and see how they do.

To cut the tubing, I used the ever-nifty MetalGeek templates...You print and cut them at 100% scale, and then use them to mark what part of the tube should be cut to mate up.

http://metalgeek.com/static/cope.pcgi

Once I had things more or less attached, I bolted the Nissan arm to the mount plate, and then drilled another hole for a second bolt to prevent movement. I would have just welded the parts up, but I don't have any aluminum!



 

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Discussion Starter #123
Well, I botched the rear mount. Now I gotta get the thing all positioned again so I can redo it. Kind of a pain, but not a show-stopper. Measure twice and all that...It needs to be about a half-inch lower to avoid hitting the steering rack. Really thought I had that sorted.

I hope to get the motor in this week, then on to axles, brakes, and actually making wheels spin on command...

 

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Discussion Starter #125
I got the motor mounts fabbed and subframe installed (I think)...Hopefully for the last time until it's on the road and legal. The subframe seems to lean back about 5簞 or so...I had assumed it was supposed to be level. I can't imagine it'll mess with anything, but...good to know.



 

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Discussion Starter #127 (Edited)
The motor is in! It had to go in from the bottom...It just wouldn't fit from the top.

I won't know for sure until it's on the road, but it's pretty damn level, pretty damn square, and pretty damn centered (in terms of axle output). There's even space for coolant lines, which I was worried about.

I wish I had given greater consideration to installing the motor with the subframe in place. It wasn't too crazy to fit, but it involved more levering and maneuvering than I'd like, and it wouldn't have taken too much effort to improve. Having a crane was very handy, though a transmission jack would have been handier...Maybe I should have installed everything into the subframe and installed the whole thing, but that seems like a much bigger operation anyway.

All of the bolts are accessible without too much hassle, although I could not get the middle bolt of the three on the right side motor mount in (the subframe blocks the hole, and the motor can't be installed with that mount arm attached). I assumed I'd be dropping it in from the top without measuring engine bay clearance!

I shouldn't have bothered with the OEM mount arm on the right. It's just too big. Shoulda just made a steel plate like the others.

Now it's on to reinstalling the suspension, measuring to have axles made, figuring out what to do about brake lines and the inverter hitting the booster, and getting this thing to spin on command!















There is a clearance issue I hadn't anticipated...The rear motor mount plate that bolts to the motor is touching/chafing the body a bit. I'm okay driving on it until the car is legal, but it does defeat the purpose of all the rubber motor mounts! My problem is solved by cutting/grinding away the top 1/4", but it could have been a lot worse if the motor had been even slightly further back.



I also had to chamfer the outer tower edges a bit, as they were digging into the body a smidgen near the shock top mount. No biggie, I did it in place.

 

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Discussion Starter #128
The inverter doesn't fit. Not a shocker. I see two options:

1) Put it in sideways, fab a bracket so it bolts up.

2) Put it behind the front seats.

If I put it in the rear, it means I can put some batteries up front, which should help keep the weight distribution biased towards the front (the batteries are more dense than the inverter). The down side is plumbing coolant lines into the cabin and more heavy wiring.

I'm gonna mull and get the suspension and brakes together (which might take quite a while). Then I can weigh the car and see where it stands.





 

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Be wary of locating the inverter too far away - the encoder is really susceptible to noise and should be as short as possible (real world experience of this)

Sent from my SM-N976B using Tapatalk
 

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Discussion Starter #130
Interesting...What's an encoder? I thought all the magic happened between the inverter and controller, and the inverter just pumped out power on those three big cables, such that the only concern would be heat and voltage drop...
 

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Interesting...What's an encoder? I thought all the magic happened between the inverter and controller, and the inverter just pumped out power on those three big cables, such that the only concern would be heat and voltage drop...
The rpm/position sensor in the motor bearing. There is also a few temperature lines in there. Its the harness that runs between the PDM, inverter, motor and back to the bulkhead.

Sent from my SM-N976B using Tapatalk
 

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Discussion Starter #132
Ah, I seethe CAN stuff. I'm hoping that using CAT5 (or even real twisted CAN wiring) will give me a few meters without too much noise.
 

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Discussion Starter #133
The suspension is back in! I had to buy new lower arms to fit the McGee subframe. The rest is still using the janky rubber and worn-out joints I pulled off the car. It feels icky putting them back, but I'm certain they'll have to come off again in the near future, so I figured I'd get the car driving and corner-weighed before I bought more shiny stuff.

I had to grind away a bit of the Leaf flange to get the joints out (even though I won't be using them).



 

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Discussion Starter #134
AXLES!

I'm sourcing custom axles from The Driveshaft Shop, and there are some surprises.

The first is where to measure from...The "normal" output is measured from the tip of the rubber seal for some reason. The output with the intermediate shaft is measured from the inside of the bearing race...I was measuring from the outside.

As a result, I believe my motor is about 1/2" too centered. I'm also not certain that my measurements equate directly to shaft lengths...I'm hoping that the the in/out travel of the CV joints, combined with the limited suspension travel of the Mini, will still allow me to use shafts of equal length, but I dunno. I measure 18" and 17" with the axles parallel to the ground. I measure 17.5" and 16.5" at full droop. I'll know more once I get the axles, but that might be a weeks.





The Mini side was measured with the spacers in the hub pushed as far inward as they'd go.



The second surprise is that they don't just fab an axle and ship it. They modify the existing Leaf bits and send complete axle assemblies (they seem to have their own shafts that work with classic Mini hubs as well). So, I'm gonna send them my Leaf flanges and get back a complete assembly (hopefully)!



Cost is about a grand. I feel better about it than trying to sleeve/lathe/drill the Mini and Leaf axles. I don't have that skill, and whoever does in LA will charge hundreds anyway...Mini axles tend to snap along the circlip ring near the wheels with much torque...and the Leaf will put 2-3x the torque to the axles vs the stock motor (and this is at a dead-stop). At least I think I ran these numbers right...Comparison to the most monstrous Honda B swap:

Mini MPI: (70tq) * (3.44 1st) * (3 final drive) = 660-720tq to axles
Honda B: (140tq) * (3.23 1st) * (4.4 final drive) = 1900tq to axles
Honda B: (140tq) * (2.1 2nd) * (4.4 final drive) = 1295tq to axles
Leaf: (210tq) * (7.91 final drive) = 1,660tq to axles

On to getting the motor to spin with a throttle!
 

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That's some great info on driveshafts. I should have some outlander driveshafts coming soon and I've managed to find someone who can machine and weld them for the mini.
I may only use them as a mockup and look into the costs of proper shafts.
As you stated minis aren't used to this amount of torque from a standstill.
 

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...Mini axles tend to snap along the circlip ring near the wheels with much torque...and the Leaf will put 2-3x the torque to the axles vs the stock motor (and this is at a dead-stop). At least I think I ran these numbers right...Comparison to the most monstrous Honda B swap:

Mini MPI: (70tq) * (3.44 1st) * (3 final drive) = 660-720tq to axles
Honda B: (140tq) * (3.23 1st) * (4.4 final drive) = 1900tq to axles
Honda B: (140tq) * (2.1 2nd) * (4.4 final drive) = 1295tq to axles
Leaf: (210tq) * (7.91 final drive) = 1,660tq to axles
I didn't check the multiplication or the transaxle specs, but the logic looks right and the end values are not surprising.

Although "monstrous" for a Mini, the Honda specs are ordinary for compact cars. This confirms that EVs are not magically acceleration beasts compared to ordinary gasoline engined cars (especially considering their high mass)... if the gas car is actually shifted for best performance.

It's too bad that someone decided that "torques" is a unit of torque measurement - it's not. Torque is a type of physical quantity, like speed or power or temperature. As with any quantity, there are many possible units of measure; these values are presumably in pound-feet (lb-ft or ft-lb).
 

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Discussion Starter #137
Oh, hayeah. I just use tq because I don't like typing or looking at ft-lb. These were copy/pasted from my notes.
 

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AXLES!

..Mini axles tend to snap along the circlip ring near the wheels with much torque...and the Leaf will put 2-3x the torque to the axles vs the stock motor (and this is at a dead-stop). At least I think I ran these numbers right...Comparison to the most monstrous Honda B swap:
I call bullshit on the mini axles snapping - there are lots of things in that drivetrain that are weak - but the axles are NOT one of them

I would also say that you don't need to worry about extra loads on the axles as you are limited by the amount of grip that you can get from the tyres

ESPECIALLY if you stick to mini suspension geometry!!

Even with racing slicks the amount of grip is simply not that great
 

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Discussion Starter #139
I concede, but some Brits disagree:

http://www.theminiforum.co.uk/forums/topic/346895-drive-shaft-removal/

I think it's more about slippery surfaces changing quickly to a sticky surface at full throttle, as opposed to motor torque dragging the car forward from a stoplight...

If I could lathe, sleeve, weld, and balance them myself, I wouldn't think twice about using the Leaf and Mini shafts.
 

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Discussion Starter #140
Weight distribution sanity check! I was thinking about where to put the inverter, and I was afraid I was way ass-heavy, so I put the wheels back on and put it on the scale. The car had seats, the inverter in the engine bay, no axles, no brake calipers.

Stock (with empty gas tank):
494 509
298 276
Total 1,577 (64%/36%)

As it sits:
360 440
390 330
Total: 1500 (53%/47%)

With two 150-pound passengers, the distribution stays the same.



I'm pleased. I was aiming for a "worst case" of 50/50, erring on the side of more weight up front. It seems that weight hasn't shifted too much. If I add the full pack to the rear, I'd be moving things back around 2-3%, and that's with the batteries just sitting on the rear seat instead of on the floor forward. There is also some space in the engine bay for a small pack or two of batteries.

It seems like I'm in a good spot with some options for shifting things around without too much hassle. I still plan to put in AC equipment, as well as a hood, radiator, pump, coolant, etc, so this means I don't have to run coolant into the interior, which is nice. No sealed battery boxes...I'm just gonna fab up some mounts for the inverter, and then wire it in with a throttle...

Better power-to-weight than a Mustang GT...if I can get it to the ground...
 
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