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I have been lurking and this is my first post. I have read the nuwiki and all the faqs I could get my hands on. It's all been great information and I'm grateful for the site.

I want an electric car. I don't want to buy some OEM vehicle. I want a project. I don't want to convert a full size car. I can't see moving a 3000 pound car to go 65 mph just to get around town. Also, I live in Tucson and we don't really have freeways. Also, it's quite temperate, so I don't need to worry as much about the elements, not to mention the prospect of tapping into a solar panel/storage system (my next project). Frankly, I like high speed golf cars, but they only go 25 mph and I'd like to go about 40 mph to and from work. I'd like to have a 40-50 mile range, but I could get by with less. That being said, going 40 mph in a golf car is a a bit of a risk.

The Ford Think NEV is a large golf car. It has a wider and longer wheel base. It has four wheel independent suspension. It has an aluminum frame so it is light weight. The main problem with it is that it has a faulty controller, motor, electronic system. I constantly hear about guys having ongoing problems with the electronics. Also, Even with the stouter motor and second generation controller, it doesn't quite go fast enough for city driving (35 mph). Not to mention that it's a wide open golf car that really needs a roll bar or frame to be a little more safe.

The other concern I have is about dealing the Arizona Department of Motor Vehicles. I don't want to make a car from scratch because i'd have to get an inspection and i can't stand state government. I work for state government and know the score. The best thing to do is to avoid them by sending them money :) You got pay for tags and keep your vehicle insured so they leave you alone.

I bought a registered Ford Think roller (see photo A). It has none of the body parts. It has been gutted to everything but the rolling chassis. It has a title. It has the Arizona plates. I pay the insurance on it even though it isn't running so the government doesn't think it's uninsured and require an inspection.

My plan: move the seats to the floor board, run the batteries down the middle of the car(t), tilt the steering wheel, chop the roof down to be a sport car sized vehicle, and add a roll cage. I will then put a larger motor on with more voltage to go faster. I'm figuring I will end up with a lightweight electric rail dune buggy type of vehicle for the street only.

I also plan on using SLA maintenance free batteries. I desire this simply to avoid the hassle of checking batteries levels.

Some of the concerns I am having is that the starting configuration will be with no transmission. The quickest configuration will be a direct drive to the existing Ford Think differential. It has a 10.3/1 ratio. The other main concern will be that the side beam of the frame is somewhat close to the differential (see photo B). I need a motor that is shorter in length and perhaps larger in diameter. I only have 10.25 inches of clearance from the differential mount to the end of the motor. I wanted to go with buying an AC motor, controller, charger package. The AC motor will cut down on maintenance and although the package might add to the price, it will be a combination more likely to have a proven track record. Regardless of AC of DC, package or not, I would like any motor that is no longer than 10 inches regardless of the diameter. I have come up with a work around: I could rotate the differential (see photo C), cut away some of the frame (see photo D), perhaps reinforce the frame, and mount the motor under the side beam of the frame. This will allow me to use any motor up to 13 inches in length.

My other barrier is how to "mate" the 19 tooth spline shaft (see photo E) to the straight gear shaft on whatever motor I buy. I am a welder and I can turn a wrench. But I am not a machinist. I suppose I'll have to make contact with a gearhead to figure out how to do this. It would great to find something off the shelf. Any suggestions anyone has would be welcome.

Any suggestions on an AC motor, controller, charger package would be great.

If the photos don't show below, I apologize. The photos are in my public album. The HOWTO says to use the BB code from the album but when I did that, the photos didn't show up in the thread editor.

 
Photograph A


Photograph B


Photograph C


Photograph D



Photograph E
 

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cute. hpevs has some 19 spline ac motors, might want to talk to them or a distributor to see if it will fit.

also used think motors are a couple hundred on ebay.
 

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I can give you some help, or perhaps the road blocks you are going to run into. I bought a Ford Think about 6 months ago to convert into a very fast golf cart. I gave up because there was too many obstacles. Mainly because most everything you will need will have to be custom built. That is why I used an EZGO frames as there are hundreds of manufactures that make parts, upgrades, and accessories.

Lets start with batteries. I advise you to reconsider battery types. To get the kind of current you are going to need with your limited space and weight restrictions Pb batteries are not going to cut it. Example lets say you choose to use something like Trojan Ranger a 8 volt 160 AH battery in a 48 volt configuration is going to weigh 460 pounds, with only 80 Amp hours usable. Any acceleration greater than 100 amp sis going to incur a very large voltage sag (You are going to need 500 amps to accelerate). A set of 6 Trojan Ranger is going to cost roughly $1000 to $1200.

For the same money you can have a 16S LFP 100 AH battery that takes up half the space and and 1/4 of the weight at 120 pounds. In addition more usable capacity, and no problem with voltage sag under heavy acceleration. It is a NO BRAINER decision.

Next your differential ratio is such that obtaining the ground speed you desire difficult. You really need about 5:1 if you use a Golf Cart DC motor, and 6:1 if you use a high RPM AC motor. This is one of the road blocks. Absolutely no problem if you had a standard golf cart differential because there are hundreds of places to get the replacement gears. You have one of a kind differential no one makes parts for. You would have to have a machine shop custom make you the gears.

As for motor choices there is DC and AC. Of the DC motors you are pretty much SOL. All DC motors made for 19-spline are series golf cart motors. That means fairly low RPM of about 5000 RPM max. With your differential gear ratio puts 35 mph pretty much out of reach unless you use a lift kit that does not exist to allow you to use larger wheels and tires.

However if you use say an HPEV AC9 or AC15 motor you can get your 35 mph because the RPM limit is much higher of 8,000 RPM. Catch is the AC motor cost about 3 times more than DC, and the Controllers are also about 2 to 3 times higher than DC controllers. An AC9 with 650 amp controller is going to set you back $2500.

Tell you a little secret. For less money than you are going to spend trying to make this thing work, you can buy a used EZGO 2FIVE and remove the RPM limit via controller programmer and replace the speed gear and have your 35 mph. Just removing the RPM limit in the controller will get you 30 mph. Remove the RPM limit and change gears you get 37 mph. You get a real road legal NEV you can title, has DOT windshield, 4-wheel disc brakes, seat belts, lights, mirrors, and horn. Additionally tons of OEM add-ons and accessories for sale everywhere.
 
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