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Also, I am considering a dual motor setup (not connected to each other, rather one motor for each side of the rear axle). My understanding is that this would give me more torque with less current. Is this correct? Is the extra cost worth the performance gains?
Comparing one of a motor with two of the same motor with the same overall drive ratio - regardless of how the connection to the wheels is mechanically arranged - is doubling the amount of motor. That certainly changes the performance (including doubling the total torque available), but I don't know why that would be assumed to reduce total current demand.
 

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Two motors is a bad idea because you will then need two reduction gears
And you will also need two controllers, programmed to work together.

But you don't need a differential, and you can control side-to-side torque distribution in controller software instead of mechanically complex (and not highly controllable) differential mechanisms or with friction brakes.

For equivalent performance, each motor, controller, and gearbox of the split design can be half the power of the equivalent components of a single-motor design.

While separate motors has production precedents and is the direction of the future, it seems like a bit much for a novice project. The details of controller programming and the challenge of finding suitable gearboxes without differentials in single quantity could easily be overwhelming. Perhaps this approach should be left to a second project... a few years from now when Tesla Roadster 2 rear drive units become available as salvage.
 

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On the other side, I have been looking at other AC motors and am intrigued by the HyPer 9 (from NetGain) and the Siemens Azure 1PV5135 4WS14.

Both motors are comfortably within my budget and was wondering if anyone has any experience with them (Performance, ease of installation, etc.)?
The availability of the Hyper9 was announced in this forum less than four months ago. I haven't noticed anyone posting that they had built anything with one.

In contrast, that Siemens motor has been around since the days of the long-gone Azure Dynamics.
 

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For batteries, kind of confused by Leaf Modules (with the 2 cells in series, 2 in parallel thing they got going on). The specs seem somewhat underwhelming compared to other battery cells.
Compared to other cells used in production EVs which need to actually work, or compared to the claims associated with cells offered for sale to DIY builders in competition with other claims on websites?

See Duncan's comments about expectations for reliability...
 

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I'll also check out that BMW build.
This one: Tesla Powered BMW E31 8 Series
Sure, it's an interesting project, but note that neither of your target vehicles have a suspension and structure - at either end - which is anything like the ideal semi-trailing-arm RWD setup of the previous-century BMW. The front suspensions are not arranged to fit around a drive unit which is wide in the portion behind the axle, and the rear suspensions are not set up to be driven at all.
 

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A good bet for a FWD car, especially a CRX is to transplant a rear-wrecked leaf drivetrain.
https://www.youtube.com/watch?v=d_r_HKV_ZgQ
I agree that the Leaf powertrain is a logical fit to a typical transverse-engine front-drive car. Of course mounts will likely all be in the wrong places. ;)

It's hard to find useful information in random videos, but using the name from that YouTube page some searching found...

NEDRA (SC) Street Conversion Record Holders
"Far From Good" 1988 Honda CRX
462 volts
Owner / Driver: Arlin Sansome
Sponsor: Underground Electrics

Time (sec) 12.683
Speed (mph) 116.9
NOPAC, Mission Raceway, Mission, BC
September 8, 2017
Facebook post by Underground Electrics
The CRX is consistant at 300+hp at the wheels, with the peak torque at 295 ft-lbs (motor) which is 2349ft-lbs at the wheels! I know I can get more and we tried to play a bit but as always time run out with everything being a cluster...
I took many people for rides and they were all blown away! The Dyno operator said it was the coolest car he has dyno'd :) All and all a good day. Oh and they had a Z28 come in after me... He was bragging nothing was stock and this and that he figured as much as 700whp lmfao.... I posted his run on my youtube channel lol
https://www.youtube.com/watch?v=S6OInkLWAhk
 
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