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Cons: worse efficiency, bad torque, slow acceleration, possibly overheat motor

The road speed at which you reach full motor power will be twice as high.

Above that torque-limited range (about 0-2800 RPM for the Leaf motor), the ratio difference won't matter to performance, but the motor will be running at half the speed and twice the load as it would be with usual gearing, and that will shift it to a different point in its efficiency map. The most efficient operating point for the Leaf motor and controller system is in the top half of its speed range, which you'll never see in use with the tall gearing.

A roughly 2:1 reduction gearbox between the Leaf motor and the traditional final drive unit would be good combination, but those gearboxes (such as the ev-TorqueBox) are not cheap.

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No, worse, due to lower motor efficiency at lower speed and higher torque.I suppose this would not result in better power consumption either.

To be fair, I used "half" and "double" as a really rough approximation of the ratio of the ratios.I was hoping for at most, a moderate reduction in torque. Not as bad as stated.

If you have 8.193:1 Leaf gearing and are considering a 5:1 final drive (which won't be exactly 5:1), it would be 5/8.193 or 61% of the torque, in the torque-limited speed range.

That's nominally (215 x 0.75 x 2 + 15 x 25.4) = 704 mm tall (TireRack shows one example at 722 revolutions per mile).The current tires I'm running are 215/75-15

Stock Leaf tires vary by year and trim, but include 215/50R17, which are (215 x 0.50 x 2 + 17 x 25.4) = 647 mm tall (TireRack shows one example at 815 revolutions per mile).

So even with the same gearing, the motor in the LT will turn at about 90% of the stock speed (for the same road speed) and will get 90% of the drive force to the tires (with the same gearing, so the same torque, in the torque-limited speed range).

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And that's with the stock Leaf gears. It really looks like I need to maintain 9:1 or better yet 10:1. At $3500US, the planetary reducer is difficult to swallow. Best I just get this beastie on the road with the VW T4 subframe (full leaf motor and gear reducer) I already have made up. Just waiting for the body to get media blasted so I can finish the bodywork. I was hoping this would save time. Oh well.No, worse, due to lower motor efficiency at lower speed and higher torque.

To be fair, I used "half" and "double" as a really rough approximation of the ratio of the ratios.

If you have 8.193:1 Leaf gearing and are considering a 5:1 final drive (which won't be exactly 5:1), it would be 5/8.193 or 61% of the torque, in the torque-limited speed range.

That's nominally (215 x 0.75 x 2 + 15 x 25.4) = 704 mm tall (TireRack shows one example at 722 revolutions per mile).

Stock Leaf tires vary by year and trim, but include 215/50R17, which are (215 x 0.50 x 2 + 17 x 25.4) = 647 mm tall (TireRack shows one example at 815 revolutions per mile).

So even with the same gearing, the motor in the LT will turn at about 90% of the stock speed (for the same road speed) and will get 90% of the stock torque to the wheels (with the same gearing, in the torque-limited speed range).

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In your case, if you still have the gear box in the truck, and the drivetrain is not in the way of batteries, I would use that. Many of the people doing landrovers that I talk to are taking that approach. At least you have some gears you can pic from.

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