How to determine power (volts/amps) needed for top speed.

I'm currently an armchair enthusiast looking to learn more about the relationship between a motors power and the controller driving it.
For example if I wanted to put a Nissan leaf motor in a small SUV like a ford escape, I can calculate the rpms needed after the read diff. to get the top speed I want(I'm a traditional ICE guy with a decent amount of experience so some aspects are similar). But I can't seem to find data sheets for the leaf motor that show shaft rpm at certain volts/amps. Is that determined by the controller used? I had decided against the leaf motor because I thought it would be underpowered, but then stumbled on the axiom controller/ Arlo1 build and am more confused about how to accurately determine the power a motor can produce and what's required for that power. The largest hurdle I will face is the battery pack so I think starting with what the motor needs and then matching the pack to that is the best route. If this question has been answered elsewhere please direct me .

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btdale said:

I'm currently an armchair enthusiast looking to learn more about the relationship between a motors power and the controller driving it.
For example if I wanted to put a Nissan leaf motor in a small SUV like a ford escape, I can calculate the rpms needed after the read diff. to get the top speed I want(I'm a traditional ICE guy with a decent amount of experience so some aspects are similar). But I can't seem to find data sheets for the leaf motor that show shaft rpm at certain volts/amps. Is that determined by the controller used? I had decided against the leaf motor because I thought it would be underpowered, but then stumbled on the axiom controller/ Arlo1 build and am more confused about how to accurately determine the power a motor can produce and what's required for that power. The largest hurdle I will face is the battery pack so I think starting with what the motor needs and then matching the pack to that is the best route. If this question has been answered elsewhere please direct me .

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Have you tried this : https://www.ebikes.ca/tools/simulator.html?

Lern about the relationship between gear ratio, speed, and wheel Tq. Input power ( to a transmission, final drive, anythig with a ratio) is congruent across all like loads.

ICE are rated in Kw. Along with the equivelent "Hp". EV rated in Kw. Most of this is determined by the supply of the controller.

Motor rated in "Kv". This is the RPM generated/ volt. So for a "8" Kv motor, at 1 volt, motor turns at 8 rpm, and the controller determines the power ( and hence acceleration speed) of the revolution. 2 volt, you get 16 RPM. this is an oversimplification.

Knowing what Hp needed for acceleration is also an important figure to know. This is described traditionally between a "close ratio" and a "wide ratio" gearbox in an traditional ICE. Electrically, it is still important, but no longer a mechanical ratio, now it is a ratio between current, load, and power. Ever see a ZX10R with a wide ratio gearbox, or a truck with a close ratio box? Lol......

Leaf motor will be rated for a voltage, and a Kv. Tq. is produced against load in an electric motor.. so.. to simplify, you use AMPS to SPIN UP but then the AMPS drop when the LOAD decreases at desired traveling speed. If you want to race or rally cross you need speed and that takes more power and the Kv/ voltage relationship must accommodate the numbers desired.

Takes power to get up u to speed but not to spin at that speed. No load RPM. When loaded, power increasing and tq transmitted until the max of the ratio.

Theres more to it, but this is a simple way of describing the relationship.

I think. Just a amateur builder, so if someone wants to correct me...

So in an electric motor in simplest concept
Amps relate to torque (what melts things)
Voltage relates to motor speed (what makes it fly apart or shoot a lightning bolt to ground)
Kv is motor RPM per volt
And you can increase voltage to get more power (watts/kw) for the same amps

So for the leaf...
Motor top speed - 10,390 rpm
Pack voltage - 360v
Rated power 80kw/107hp (360v@222amps?)
Single gear reduction 7.94
Of note it looks like the stock configuration cant spin the tires faster than 95mph.
With these numbers the drivetrain really looks like a 2:1 scale hot rodded golf cart, so for the battery pack investment id look at takeout tesla gear unless you got a free/stolen leaf, my 2 cents.