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Hi Mschoen,

I love that motor. I designed it, back about 1978 or so. For Jet Industries Electra Van. Small Subaru highway capable 4 passenger, 96V, 16 golf cart batteries and like the first mosfet controller for EVs (PMC I think). Jet Ind was in Austin, TX. Great motor in 7.2 inch diameter frame. Set up with factory brush advance, 4.5°. NASA did test it, see link from KB. They wired it opposite rotation from intended and no evidence they compensated for advance. So test results were not optimum. We did indeed verify 200 A continuous with forced air cooling.

After Prestolite production run and delivery, Jet switched to a GE 9" motor package with controller. Looks like seller ended up with excess inventory. Hell of a good price. She's a screamer at 100V but holds together. Could go higher voltage but limit to 6000 RPM. Even for a 40 year old motor, should be good to go right out of the box, with break in period. Careful of no load overspeed at full voltage. She'll accelerate like a banshee.

Nice find,
major
 

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1968 Fiat 850 Spider
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Discussion Starter · #4 ·
That is so great to know! Who would've known that you would end up seeing these again! I will definitely jump on one then and let you know how she goes! I am putting it in my 1968 Fiat 850. Rear engine car so the motor would need to be counter-clockwise in rotation for drive, otherwise I will have many gears of reverse! ha! Also appropriate to have an era aged electric motor for a close in year car.

I do not plan to run this motor crazy, but as long as I can get to 65-70 mph comfortably to make the highway, I will be more than satisfied. Otherwise, this will be a Sunday cruiser for most of its life. No drag strips for me.

When you say 16 golf cart batteries I am assuming you mean the 6v size? I would like to use Nissan Leaf modules. I can actually fit 27 in the engine compartment above the motor. Perks of a low laying set up. That would give me just under 200v total. I Hope I can find a controller that can handle the 200 and bring it down to the 96 for frequent use without burning it up.

What kind of controller did you say? I am new to this so the acronyms are tough sometimes haha. I also do not think I will be pushing 200A continuously, but I can easily hook up a temperature controlled fan to cool it if I do get to pushing that kind of amperage. Maybe I will though, still doing some math on these modules with the DC. I am no electrical person by any means, so knowing how to pick pieces that are strong enough is kinda hard for me. So, I do apologize for my ignorance on certain things!
 

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At $180, that is super cheap for a new old stock 7 inch DC motor. It says C face. I assume that is smaller than the typical B face used on the Warp series and other 9 inch motors and the transmission adaptor plates for those.
 

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@Mschoen,

Do you know the gear ratio of the trans and differential, plus the tire size for your conversion? From that you can calculate the required motor RPM to reach 60-70 mph.

Also what will be the weight of the car, and what is the aero drag coeff and frontal surface area? From that you can calculate the power required to maintain that speed.

Looking at the test curves, 200 Amps makes about 25 ft-lbs of torque.

96V and 200A is about 20kW or 25Hp input power, and with that it makes about 17Hp at about 4,500 RPM output.
 

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1968 Fiat 850 Spider
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Discussion Starter · #9 ·
Well the car is a read engine, so that means I have a transaxle. The final drive gear ratio is 4.88:1 and top gear ratio is .96:1. It is a 5 speed manual, so I would probably keep it in 3rd gear which is a 1.96:1 ratio. As for the weight, the factory says 1600lbs but that includes the gas engine and a full gas tank. So I think it is safe to say that the car would weight about the same with all the modules, the motor(the motor is just over 100lbs), and all the other components. The tires are 5.5"x 13". I am not sure of the drag, but this car is super low to the ground and has a flat nose.

This is what it looks like. Not my car, but an example.
https://www.google.com/url?sa=i&url...ved=0CAIQjRxqFwoTCMDWxLuDmOoCFQAAAAAdAAAAABAM
 

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1968 Fiat 850 Spider
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Discussion Starter · #10 ·
Just ran my numbers through an online calculator.

With a ratio of 1.96:1(that is third gear), tire size of 13" and wanting a speed of 70 mph would mean that my RPMs would be 3550.

Seems pretty achievable.
 

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1968 Fiat 850 Spider
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Discussion Starter · #11 · (Edited)
Also found a calculator for power to maintain speed.

Estimated coefficient of drag .31, front of car being 16 sqft, 1600lbs at 70 mph means that I need to have 15.5 HP to maintain that speed.

Also seems very achievable
 

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Discussion Starter · #14 ·
A lot has happened since I posted here last. I do have a couple questions for @major though. I did purchase the Prestolite motor and is actually being delivered today! I wasn't expecting it for a week! I also got an evnetics solitron jr controller that I am very excited about. Now my question is, the controller asks for a proximity sensor. Obviously this motor doesn't have a post on both ends for a sensor to read from, so I thought to place it near the coupler in the bell housing on a bracket. Would you happen to know of a better place to mount it? Is there a way to add a post from the end? Since you were so involved with it's development I figured you would know best! Thanks!
 

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As for the weight, the factory says 1600lbs but that includes the gas engine and a full gas tank. So I think it is safe to say that the car would weight about the same with all the modules, the motor(the motor is just over 100lbs), and all the other components.
A conversion rarely comes out with a weight as low as the original, and especially not with enough battery for useful range. Occasionally the original engine is such a boat anchor that the conversion doesn't increase weight (a cast iron inline-six, for example), but that's rare, and the 850 engine should be light... it might not weigh much more than just the electric motor which replaces it. One 850 owner who removed the engine says it weighs about 150 pounds. The controller, wiring, and EV accessories (DC-DC converter, charger, BMS, etc) will weigh 50 pounds, so the motor plus that stuff is as heavy as the engine, and so every bit of battery weight beyond a tank of gas is an increase over the car's original weight.

I'm a bit surprised that an 850 Spider weighs as much as it does. I believe the 1600 pound specification (it's readily available online), but for such a small and basic car it seems heavy; a basic first-generation Honda CR-X is the same weight, in a larger car with almost double the engine displacement and 1980's construction and safety equipment. The 850 must have lots of cast iron components. It is likely handicapped by sharing chassis components with the larger body styles of the 850, which even included a 7-passenger van; on the plus side, that might mean that chassis components can handle the extra battery weight.
 

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Discussion Starter · #16 ·
That is a great insight. I never thought about it that way. It doesn't have a chassis per say, but the uni body has a massive X brace under the passenger compartment. The body panels are also thick compared to modern cars so I think that adds into the weight quite a bit.
 

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1600 lbs is 727 kg - I don't want to rain on your picnic but that is actually very light - the old classic Minis were about 650 kg - so 727 kg is probably about right
My car which is very basic is 805 kg
 

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1968 Fiat 850 Spider
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Discussion Starter · #18 ·
I can barely bump this thing and it rolls! I bench tested the motor yesterday and it was great! I posted it on my project's instagram. 850_ev_project if anyone wants to see and follow along!
 

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Discussion Starter · #19 ·
That's so cool! I didn't know they went into production. I received the motor and has to pop off the end of it to clean the surfaces. The ends of the connectors were stuck and had a loud noise. After cleaning it, things were much quieter. I have a video of the motor and trans tested together on Youtube if anyone is interested.

 

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Dude: that is a lot of movement! And noise! How did you line up your adapter plate? Most OEMs call for no more than 0.005" side to side misalignment in the ICE/ transmission set-up and the transmission input shaft needs to be carefully supported on its end(in your case there is a smooth round section for the pilot bearing to ride). The EV Gods don't grant you any waivers from having to maintain these tolerences and support.
 
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