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Discussion Starter #1
I have purchased a 1995 Mazda b 2300 small truck with the intent of converting it into an EV. Purchase price was $ 650.00 with a blown motor on 7/15/2009, the seller bought this truck at an auction, untested, just to discover that it has a serious problem, blown piston ,rings, or valves, who knows, it did run but smoke, whooiee!!! it has new paint and a fairly clean interior, 4 speed trans/w overdrive, manual windows, manual steering, and drove fairly well, I was afraid on the test drive that it was going to throw a rod at any time, so I towed it home!

At present (July 29, 2007) I have removed, hood, radiator all hoses, exhaust manifold, and all wiring harnesses, ( 2 hrs work). I have reviewed Bob Braynts book as well as the el moto motorcycle book ( which was entirely to expensive for the 40 page leaflet style thing they sent me, $40 I do not recommend it!!) I haven’t got this thing totally mapped out yet but I am leaning toward the warp 9 impulse motor from Netgain, and the zilla controller and a 144 volt configuration. What I would like to do is remove the motor, trans, and driveline and mount the motor on a plate above the 3rd member ( differential) and use a direct drive configuration with a ribbed belt and drive wheels for a total reduction of 7:1 ( this seems to work well for the motorcycle( see fig #1).

Thus far I haven’t found any examples of this being done, but it seems to make sense to me. With the weight saved from the removal of the transmission and driveline and reduced length of the drive mechanism I would need to wire the motor through a reversing switch, and work out the best single drive reduction for starting and best possible speed but I’m hopeful that these are technicalities that can be worked out. Soo that’s about all I have for now all coments and help would be appreciated and I will continue to post as I progress….. thanks lou-ace.... ps I have pictures and a detail of the drive I'm considering, but for some reason It won't cut and paste here.... apologies
 

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Sounds great! 2 things tho:

1- I have never seen anyone recommend direct drive. it dosen't give you low end torque and high end speed with a DC motor. The RPM range is too small, just like the ICE u are pulling out.

The BIG one:

2- No more Zilla's. They are out of production, and claim they will be coming back. I doubt it will happen any time soon. Logisys finally seems to have their 1000amp controller to a reliable revision. I would order Straight from them.

[email protected] amps will give you lots of grunt, i myself am going for a 72volt 450 amp in my Saturn conversion.

Congrats on a solid find! Welcome to the forum, Enjoy your stay!
 

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lou-ace, I'm using toothed belt reduction drive on my MR2 but I'm only in the early stages of conversion. I'm also using two AC induction motors which have a quite different torque curve. 7:1 reduction seems a bit excessive. What's the differential reduction ratio? You may not need to reduce at all. There's a guy in Australia who did a direct drive AC induction into the transfer case on his 4x4 Suzuki http://www.evalbum.com/1149

You really need to model top speed, acceleration, etc.

Sam.
 

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Discussion Starter #4
ok guys here's an answer that I got fron the guy at Netgain "
-----Original Message-----
From: George F. Hamstra <[email protected]>
To: [email protected]; NetGain Order System <[email protected]>
Sent: Mon, Aug 3, 2009 10:14 am
Subject: Re: Contact Form

"Louis,

Our motors are reversible, however you should avoid full-power in reverse as the motors are timed for forward movement and they may arc if high power is applied in reverse.

Volts and RPMs have a linear relationship with these motors. If you double the voltage, the RPMs will double (actually just slightly more since most losses are fixed). If the amperage doesn't vary, they will produce the same torque at twice the RPM.

I do not recommend direct drive in street driven applications, ONLY in racing applications. It is VERY hard on motors to go direct drive, and "taking it easy" on the motors by only applying small amounts of power will do more damage than quick starts in direct drive applications. Unless your vehicle is VERY light you should use a transmission, and you should never use direct drive as a "first" electric vehicle as there are no mechanical safety disconnects and brakes may not be enough to stop a vehicle whose contactor or controller or throttle assembly have failed!

Sincerely,

George Hamstra "

so I think I might start listening to the experts and go with the transmission after all. naxt question. do I really need a clutch and flywheel? why not just a coupler Isn't the motor enough of a centrifical balanced force to handle the tourque alone. and SAM my rear end is 3.25:1 alone. Alexcourse I guess I need a little more education. I thought that in a series DC curcuit that the amperage stayed the same but the voltsge increases. so where does 400 -1000 amps come from..... thanks to all from the neophyte
 

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The resistance in our motors are so low, that they are basically a short. Without a controller, a motor can quickly pull thousands of amps under load, and very quickly blow up. The controller limits the current while controlling the voltage, thus giving smooth speed control.

If you take your voltage times your amperage(of your controller) you get your wattage. Divide your Wattage by 746 and you get Horsepower. DO NOT confuse this with horsepower of a gas car! They are pretty much unrelated for lots of reasons. A Corvette only needs about 12hp to do 65mph, the rest is just bragging rights.

144volts at 1000 amps is close to 200 horsepower. I'd bet your truck will break 100mph with the right gearing!
 

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I have a cutomer that has done almost what you are talking about, he has the motor with a transmission in the bed of a pickup. He has a connection through a fabricated transfercase to the driveshaft. He still has the ICE engine in its usual place, basically he has made a hybrid-electric for local driving, gas for long distance.
I think it could be done as you describe but:
you would have to mount this to the axle so it can go up
and down with the suspension,
you could put a number of safetys in the system-either electrical or mechanical (such as a clutch-either mechanical or electromechanical) in case of a problem
the main problem is the single gearing-you may run out of speed capability- with the correct gearing for taking off without heating the motor, (and drawing excess current)it may not be able to go over 45 mph without risk of overrevving the motor. A two speed trans of some sort would probably have to be used. Generally, when using a transmission, 2nd and 3rd gears are all thats needed for 99% of driving.
For a first time builder, using the stock transmission is probably the way to go-the design time for your idea will suck up many, many hours-without much benefit-but you would open up a great low area for batteries!
Mike
www.EV-propulsion.com
 

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The technicalities are minimal here. The frame lends itself well, the tranny is (per experience) an excellent match for an 8" or 9" motor. I used direct drive by the way. no clutch, no problem. 20 batteries fit no problem (5 in front 15 in back). Converted to manual steering. E powered brakes. All in all a very fun truck to build. Email if you want input. [email protected]
 

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Discussion Starter #9
Ok guys since I can't seem to update here I have:
1: removed motor,exhaust, fuel system.
2: fabricated adapter plate, found concentric.
3: shopped and am ready to buy motor............. axciting
 
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