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Hi
I'm running an 11 inch motor - direct drive to a Subaru diff

http://www.diyelectriccar.com/forum...dubious-device-44370p15.html?highlight=duncan

I'm running a Paul & Sabrina Controller - I have it set to 1200 amps and my battery pack is fully charged at 340 V

You have a brake on one end of that motor
My motor had the same splines on each end of the drive shaft
So I used the part that connected to the brake - with a simple disc adapter to bolt onto a normal prop-shaft UJ - works a treat!
 

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Hi
I have been driving my "Device" for nearly five years - initially with Headway cells and for the last year and a half with Chevy Volt cells

It's really good for 1/8th mile drags - but I'm hitting 85 mph at the end of 1/8th and I think it will blow up before the end of 1/4 mile

Page 21 of my thread has a link to my YouTube videos

I assume that your Nova is one of the old RWD ones?

That should make a superb cruiser with that motor

BUT

You may be limited in top speed - as you will be limited in motor RPM - I hope Major will speak up and tell us just how fast you can spin that motor
 

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Hi Blake
Transmissions basically go downwards - they make the motor spin faster!

In most (not sure about autos) of the old gearboxes top gear was 1:1 - straight through

Which is what you get if you throw away the trans and go direct drive!

A big advantage of direct drive is that you can put the motor where the gearbox would have gone and leave the whole engine bay for the batteries
 

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Hi Blake
If piotrsko is right then you probably have a good final drive for that large motor

Your car is about 40% heavier than mine but I suspect that you won't have a 55% rear weight distribution
3000 lbs = 1363 kg - with 40% on the back wheels you will have 545 kg on your back wheels

I have 900 kg (with me in it) - 55% on the back wheels that is 495 kg on the back wheels

My diff is 4.1:1 - yours is 2.5:1 - so I have 60% more torque

BUT you have a larger motor so you will get more torque per amp

I suspect that with 1200 Amps and direct drive you will be able to spin your rear tyres - unless you buy super sticky tyres

I normally drive mine with the 1200 amps reduced to 550 Amps - 1200 amps is just a bit too exciting on the road

Major thinks that I can get to 6000 rpm before my motor explodes - 50% higher than yours
So if you have a 2.5:1 diff which is 64% higher than my 4.1:1 - it about cancels out!

My top speed (before motor blowup) will be about 100 mph - so you should be about the same - bit higher
 

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Hi
Reverse is a bit more complex
You will have four terminals of the motor
Two for the Brushes that go to the armature and two for the field coils

To go backwards you need to reverse one pair! - reversing the whole things means you still go forwrds

To do that you need a reversing contactor - I'm using one off a forklift

To operate that motor at high speeds (the forklift or whatever it came out of would use about 1400rpm) you need to advance the brush timing
Unfortunately that means that the brush timing will be completely wrong in reverse - NOT a problem is you are just reversing
But if you want to blast backwards in an autotest it could be an issue especially as you will have the same power and speed available backwards as forwards

It's great fun being able to burn off the supercharged V8's
 

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Hi ekthor
With only 120v you won't get much power out of that beast !

And do you have a 1400 amp 400v Kelly controller cheaper than a Paul @ Sabrina?
 

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And my very efficient device (except for the aerodynamics) with an 11 inch motor would still only do 59 mph with 130v

I am willing to believe that kelly controllers no longer deserve their old reputation as boat anchors but you are still wrong about the voltage that the OP will need for his 13 inch motor

I suspect that the OP and I expect something just a tiny bit different from our vehicles than you seem to want

My device is used on the track as well as on the road
 
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