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OK so i guess i should start from the begining. Im new to the whole EV thing and have been reading a researching and coming up with ideas....crazy but who knows. It all started when a friend of mine were talking about careers and such and he said how building my own EV would be a great resume. Im an aspiring Electrical Engineer student(ive got some ways to go but still) and i am very proficient with automotive restoration and fabrication (i have an AS in auto tech) ive built numerous internal combustion engines(ICE) and know all about cars and how they run. Ive been wanting to learn more about the electrical side which is why ive chosen to go EE. so heres my project i was thinking of(sorry for the long story leading up to it):

The vehicle a 1960-62 Ford Falcon Ranchero. its a unibody vehicle that weights about 2400 pounds with the ICE. figured it would be a good little chassis to work with seeing as it has plenty of room between the bed and the body floor to store batteries.

The range im hoping to achieve (although it may be a dream im hoping with the right steps can be reality) would be somewhere around 100 miles(want to be able to make it to San Diego on a sigle charge basically)

Performance wise im hoping for freeway speeds so like 75 MPH Tops! (65+ i guess haha). the original engine in the falcon was a 91hp inline 6 so something around 100hp would probably do the trick pretty nicely. im not looking for a horsepower monster flying down the road but i am use to a V8 engine as i have never really driven anything but them(im sure i will be more than happy with an AC motor) so something that could get off the line faster than an old diesel would be nice haha

From what it looks like i would love to do a AC motor as you can get regen braking and it seems like they're getting the 100+ range out of them as opposed to DC. Im also thinking about maybe somehow or somewhere in the future there will be a way to integrate a solar roof and hood into the paint scheme and maybe get a little extra range from that.

I know it will take a while to do but im willing to do the work as long as it can be done. as far as money goes i dont want to say there is no limit as that is a lie but im willing to spend a little extra for a better motor, controller or something to that effect. Ive been really excited thinking about all of this and would love to know if it is possible with a little help for fellow enthusiasts or engineers. I dont not have the vehicle at this moment. its more of a dream/fantasy of mine right now before i decide to go ahead and make it a reality or just keep it fantasy.
 

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Welcome.

From what it looks like i would love to do a AC motor as you can get regen braking and it seems like they're getting the 100+ range out of them as opposed to DC.
Bullshit.

What will determine your range is the pack, top speed, how aero dynamic your car is, the status of the brakes and transmission etc. The efficiency of an AC versus DC system are pretty much the same so a dragging brake or rotten aero dynamics will affect your range tenfold more.

Regen will only make a noticeable difference if you live in a hilly place or do a lot of stop and go, then regen might (with emphasis on might) improve your range up to 5-10% or so, but you'll be paying something like trice the money for the same power (or, of course, pay the same but get a lot less power). If you're mainly cruising regen will do no difference what so ever for you.

And even if you might actually benefit from regen you'll probably save money on going DC anyway and add a few more cells to the pack to compensate for the lack of regen.

The vehicle a 1960-62 Ford Falcon Ranchero. its a unibody vehicle that weights about 2400 pounds with the ICE. figured it would be a good little chassis to work with seeing as it has plenty of room between the bed and the body floor to store batteries.
Weight and storage seems ok, but it's not very aero dynamic, is it? Combine that with your desired range and top speed and you'll need a hell of a pack. You might want to consider going slower or make shorter trips... :D
 

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I like the choice of caruck, 1960 example below. While AC motors are more expensive, I think they have other advantages besides regen. For example, it's easier to find one that is liquid-coolable. I'm under the impression that they may be better suited for highway speeds (higher RPMs, higher voltages, better for direct drive) but I'm sure it can be done with DC. Certainly DC motors and controllers are less expensive.

I would guestimate you'd want to have in the neighborhood of 35 kWhs worth of battery for that car. Since you are an aspiring EE, it would probably help your vehicle and education if you built a pack with pouch or cylindrical cells. If it was me, I'd aim to place it between the frame rails, perhaps raising the floor of the bed to accommodate everything.

Solar cells might get you between two and five miles of range a day. Many would say they aren't worth the cost and bother but IMHO they do make a nice object lesson. They also might look pretty cool if incorporated into a bed cover, which may also help with your aerodynamics.

 

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Discussion Starter #4 (Edited)
so what are the benefits of running an AC motor? just cooling and higher rpm? like i said im still very new and am very excited too so any info will be greatly appreciated.

Aerodynamic wise i cant see the ranchero being any worse than a xB and those are doing pretty well as an EV

My typical driving is stop and go and there are many hills to climb and descend so regen braking might not be a bad thing to consider.
As far as the mileage thing goes, you say its mainly the pack. im ok with having something a little less like 50 miles or so and than later in life getting a better pack that weighs less and powers more just as long as i know its possible to achieve i basically ok with it.
 

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There are benefits to AC motors. No brush wear, better cooling as the heat is generated mainly in the frame instead of the armature as with DC, the ability to regen, ability to run higher voltages thus reducing the amperage and electrical losses.

However, there is added complexity in the controller and the cost often outweighs the benefits for most people.

However, if you do your research and compare what you find with what you can obtain and work with within your budget and abilities then that may help focus a direction.

For a complete novice a simple DC set up is easier as the kit is available and the knowledge base is wide and parts can be found cheaply.

One member here, Simon Rafferty, built an AC powered Land Rover Freelander. His 'luck' was in going to the local scrap yard and finding an electric bus that had a motor and controller intact and cheap. He just transplanted the whole thing into the Land Rover, added some second hand scrap yard batteries and got a quick, cheap build for his 10 mile a day commute.
 

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I'm under the impression that they may be better suited for highway speeds (higher RPMs, higher voltages, better for direct drive) but I'm sure it can be done with DC.
Nope. What will get you to highway speeds is power and only power. For achieving the necessary power you need a pack that can provide it and a controller and motor that can handle it, wether you use AC, DC or hamster wheels won't really matter as long as the system's powerful enough (curious question: How many hamsters would it take to propel a Ranchero?). In the end it'll be a question of !/$, where you get less !/$ in the AC-world than in the DC-world. Also, AC can run at higher RPMs, that's sure, but since all cars are built for ICEs that seldom go over 5000 rpm you really don't have any usage for those >10k RPMs since the gearing isn't optimal for it. Besides, I'm not sure the gear box would appreciate running at twice the RPM it's made for...

Sure, there's some benefits with AC, where regen is one and water cooling might be another (the jury's still out on that one) but if you really think that AC is better suited for highway speeds I would like you to explain why for example all drag racers run DC. :rolleyes:

so what are the benefits of running an AC motor? just cooling and higher rpm? like i said im still very new and am very excited too so any info will be greatly appreciated.
I'll give you the advice I usually give in most AC versus DC threads; you have to compare systems, not technologies. You simply can't say that AC is better than DC (or the opposite), you have to compare motor and controller A with motor and controller B! If by "best" you mean "most power" I'm pretty sure the Zilla Z2k is still the winner among the controllers, but you need motors and batteries that match it too (not to mention getting hold of a Z2k which might be tricky nowadays). And, of course, a Z2k is serious overkill for a commuter...

Aerodynamic wise i cant see the ranchero being any worse than a xB and those are doing pretty well as an EV
No. You can turn a brick into an EV, no problem. It's when you combine high speed with long range you start to get problems because your kW/mile will increase with speed and somewhere around 40 miles per hour (give or take) it starts increase rapidly. Take a look at this conversion for example:

http://www.evalbum.com/2264

He's done a conversion that's pretty much what you're talking about, but he doesn't get neither the speed nor the range you desire. That doesn't mean it can't be done, of course, but I'm afraid it'll be both a technical and economical challenge.

My typical driving is stop and go and there are many hills to climb and descend so regen braking might not be a bad thing to consider.
Do you do hypermiling today? To benefit from regen you have to brake as little as possible and regen as much as possible. Try to get a feeling for how much you can engine brake with an ICE when you do your daily routes. If you do engine brake a lot then regen might be worth it for you, but since you will only be able to regen less than 50% of the energy you'd have to engine brake/regen a lot for it to be worth it. For most people it'll make more sense to forget about the whole concept, save some money by going DC and add a few more cells instead.
 

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Actually, that ranchero build has good range and speed considering he lives in the foothills where no road is flat. I know that area very well. He should be able to take advantage of regen if he gets it set up.
 

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Nope. What will get you to highway speeds is power and only power. For achieving the necessary power you need a pack that can provide it and a controller and motor that can handle it, wether you use AC, DC or hamster wheels won't really matter as long as the system's powerful enough (curious question: How many hamsters would it take to propel a Ranchero?). In the end it'll be a question of !/$, where you get less !/$ in the AC-world than in the DC-world. Also, AC can run at higher RPMs, that's sure, but since all cars are built for ICEs that seldom go over 5000 rpm you really don't have any usage for those >10k RPMs since the gearing isn't optimal for it. Besides, I'm not sure the gear box would appreciate running at twice the RPM it's made for...

Sure, there's some benefits with AC, where regen is one and water cooling might be another (the jury's still out on that one) but if you really think that AC is better suited for highway speeds I would like you to explain why for example all drag racers run DC. :rolleyes:



I'll give you the advice I usually give in most AC versus DC threads; you have to compare systems, not technologies. You simply can't say that AC is better than DC (or the opposite), you have to compare motor and controller A with motor and controller B! If by "best" you mean "most power" I'm pretty sure the Zilla Z2k is still the winner among the controllers, but you need motors and batteries that match it too (not to mention getting hold of a Z2k which might be tricky nowadays). And, of course, a Z2k is serious overkill for a commuter...



No. You can turn a brick into an EV, no problem. It's when you combine high speed with long range you start to get problems because your kW/mile will increase with speed and somewhere around 40 miles per hour (give or take) it starts increase rapidly. Take a look at this conversion for example:

http://www.evalbum.com/2264

He's done a conversion that's pretty much what you're talking about, but he doesn't get neither the speed nor the range you desire. That doesn't mean it can't be done, of course, but I'm afraid it'll be both a technical and economical challenge.



Do you do hypermiling today? To benefit from regen you have to brake as little as possible and regen as much as possible. Try to get a feeling for how much you can engine brake with an ICE when you do your daily routes. If you do engine brake a lot then regen might be worth it for you, but since you will only be able to regen less than 50% of the energy you'd have to engine brake/regen a lot for it to be worth it. For most people it'll make more sense to forget about the whole concept, save some money by going DC and add a few more cells instead.
Thanks Qer, I take your points, though if I were to play devil's advocate and answer why drag racers use DC, I would say because they only have to run for less than 15 seconds.

I'm pretty surprised by the top speed and range of the Ranchero. Can't tell what AH batteries he's using but it would seem like they're 45s. Also wish there was more info to explain why he only gets 50 mph out of it. I'm so underwhelmed.

If he was running an 11" Netgain with a Soliton 1, what kind of top end do you think he could get?
 

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I would like you to explain why for example all drag racers run DC.
Well, not just any DC, series DC motors because of their high starting torque, for high acceleration rate. Efficient cruising at highway speeds isn't the top priority for those guys, but of course many others use them to cruise at highway speeds.

I like AC and regen myself, but agree that there isn't anything available at higher power for an affordable price. The only economical AC is the stuff from HPEVS, which is below about 65 H.P. peak.
 

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that is a '63, they have different grills and hood and fenders than the 60-62. I built a '63 Falcon, with a 506ci engine.
I actually think the "square" '64 look the best.
The rancheros are pretty weak on aerodynamics, but you could make it better. Otherwise, I'd think it would be a good EV. Basically convert a car you want, not what is "best" or "cheap" or "available". It will cost thousands to convert, so you better like it when its done, cause you won't be able to sell it for what it cost to build.

AC/DC doesn't really matter much. It is all about the batteries,
and for 100 mile range, you're looking a lot of lithium, $15k worth,
maybe more at 75mph.

I like the choice of caruck, 1960 example below. While AC motors are more expensive, I think they have other advantages besides regen. For example, it's easier to find one that is liquid-coolable. I'm under the impression that they may be better suited for highway speeds (higher RPMs, higher voltages, better for direct drive) but I'm sure it can be done with DC. Certainly DC motors and controllers are less expensive.

I would guestimate you'd want to have in the neighborhood of 35 kWhs worth of battery for that car. Since you are an aspiring EE, it would probably help your vehicle and education if you built a pack with pouch or cylindrical cells. If it was me, I'd aim to place it between the frame rails, perhaps raising the floor of the bed to accommodate everything.

Solar cells might get you between two and five miles of range a day. Many would say they aren't worth the cost and bother but IMHO they do make a nice object lesson. They also might look pretty cool if incorporated into a bed cover, which may also help with your aerodynamics.

 

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It's amazing that some of the same rumors and misconceptions still prevail on a site like this, with so much technical expertise.

As has been pointed out, many times, before there is only one real drawback to using a series DC motor - you won't have regen. Whether or not that's a significant factor is a very subjective, personal, issue. Some people insist on regen. It's very important to them, so series DC is not a good choice for them.

If the system is properly designed and matched to the vehicle and intended purpose, the brushes will likely outlast the conversion (or at least the owner's interest in it). The execption is if you're a racing nut, with plans to push the motor to its limits repeatedly. If that's the case, regular maintenance shouldn't be an issue with you.

AC motors typically operate at a higher rpm, series DC typically lower. You just design the rest of the powertrain to operate in the useable rpm range of the motor you have. If you have a high-winding AC motor you "gear it down" to multiply the available torque, and still have a high enough ceiling for a suitable top end. If you have a stump-pulling series DC motor you "gear higher" (numerically lower) for more top end.


...im not looking for a horsepower monster flying down the road but i am use to a V8 engine as i have never really driven anything but them(im sure i will be more than happy with an AC motor) so something that could get off the line faster than an old diesel would be nice haha...
That, to me, is the guideline for any recommendations made for your project. If you want to enjoy driving your Ranchero as much as you have enjoyed your V8s in the past, you really should consider a DC motor. What you're describing is torque, plain and simple. Even though you're not planning to race, you want the vehicle to almost feel like it's ready to. Whenever you put your foot on the accelerator it moves - now. It doesn't hesistate, doesn't build up gradually, it just kind of plants you in the seat and gets the vehicle moving quickly.

Sounds like either a single 11", or siamese 9s - series DC. If your whole conversion is properly designed and setup it will be doing it efficiently too. In other words, you'll have the pull of a V8, with the efficiency of a small 4-banger. I know I'm oversimpifying guys - just trying to make a point. The number one thing that has to happen when this conversion hits the road is a smile on his face. He laid out the conditions that will create that smile. I just think he'd be more willing to forgive the lack of regen, or "less sophisticated" technology of the series DC, if he has that old familiar feeling when he snaps the reins.
 

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AC/DC doesn't really matter much. It is all about the batteries,
and for 100 mile range, you're looking a lot of lithium, $15k worth,
maybe more at 75mph.
For sure. AC with Regen would change range by about 8% +/-5% depending on driving conditions based on my experience. If mostly highway driving, hardly any difference at all. You will need a boat load of batteries to move a Ranchero with its relatively high drag coeff, cross sectional area, and weight very far at 75 mph. At that speed I would guess a 30kWh pack might get you 45 miles at best. Cost for a 30 kWh pack would be around $12k, and you likely need more than twice that for 100 mile range at 75 mph. And for sure if you want peppy acceleration you will need some serious H.P., which is generally unavailable to diyers in AC, or will cost $25k or more for motor/controller if you can get it, whereas the DC options "todd" describes are MUCH less costly, and will give the H.P. you want. For this type vehicle with your range and acceleration goals you basically don't have any choice but series DC motor/controller, and a small fortune for batteries. Edit: An AC controller is a little more costly to produce than a DC controller, but the main reason for the difference in cost for high power AC systems is the companies that make them don't want to deal with us generally whiny, cheapskate, diyers.:D
 

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that is a '63, they have different grills and hood and fenders than the 60-62. I built a '63 Falcon, with a 506ci engine.
I actually think the "square" '64 look the best.
The rancheros are pretty weak on aerodynamics, but you could make it better. Otherwise, I'd think it would be a good EV. Basically convert a car you want, not what is "best" or "cheap" or "available". It will cost thousands to convert, so you better like it when its done, cause you won't be able to sell it for what it cost to build.

AC/DC doesn't really matter much. It is all about the batteries,
and for 100 mile range, you're looking a lot of lithium, $15k worth,
maybe more at 75mph.
I don't personally know the year, but the website I got the pic from said '62. According to the Wiki, the body changed in 64. Anyways.. I do agree with your comment about converting the car you want. That's truly great advice.

Also, as a side note...the Aussies like their Falcon car/trucks and they kept making them so now they have a have a more aero option. Still prefer the early sixties version myself though.

 

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i just started looking into EV as well and i like you wanted an AC system but after looking around at what was available i am now firmly fixed on dc.

while AC is slightly better, more efficient, Regen, yada yada, they are alot more expensive.

AC motors here LOOK AT THE PRICE:eek:

DC motors here and here

i'd personally go either dual 9" or one 11" DC motor. Either of these motors would give you a far kick in the nuts if you gave them a chance.

This guy runs a dual 9' kostov and gets 314hp :D and motor and controller only cost him $8000. as opposed to $20,000 plus for the AC equivalent

i would also reconsider your choice of car, this guy posted a list of some examples, have a look i'm sure you'll find something you like. like this for example

But really if you had a choice of a busted up old AC ute that crawls of the line and barely reaches 65mph, and a sleek 2 seater DC sports car that pops wheelies of the line and screams to 60mph in well under 10 seconds what would you choose?
 

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...i would also reconsider your choice of car...
Your post had a lot of good advice, but then you lost sight of his goals.

...It all started when a friend of mine were talking about careers and such and he said how building my own EV would be a great resume. Im an aspiring Electrical Engineer student(ive got some ways to go but still) and i am very proficient with automotive restoration and fabrication (i have an AS in auto tech) ive built numerous internal combustion engines(ICE) and know all about cars and how they run. Ive been wanting to learn more about the electrical side which is why ive chosen to go EE. so heres my project i was thinking of...
...The vehicle a 1960-62 Ford Falcon Ranchero

...im not looking for a horsepower monster flying down the road but i am use to a V8 engine...

...Ive been really excited thinking about all of this...

...its more of a dream/fantasy of mine right now before i decide to go ahead and make it a reality or just keep it fantasy.
It's not for daily transportation. It's a toy/dream project. More hot rod than commuter EV. Switching to a more generic body for better aero efficiency will subtract enthusiasm and enjoyment.

Not trying to be a prick, just trying to keep the conversation focused on the actual goals of the project. I've noticed that people often reply to questions with their personal goals in mind. You have to keep the OP's goals in sight to really help them.
 

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I've noticed that people often reply to questions with their personal goals in mind.
fair point. I was trying to point out the differences between AC and DC setup and a few places he could find them, and i guess i got carried away.

my computer kept crashing halfway through the post and i forgot to mention the different ranges the cars had, with the more efficient ones getting twice the range for the same cost. the goal was for him see the difference aerodynamics can make. yes the Toyota was my pick.

still i stand by the decision that the ford falcon rancho wouldn't easily make 100miles, not to say that it wouldn't be a fun ev. If it did, you could get the same distance for a fraction of the price.
 

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...still i stand by the decision that the ford falcon rancho wouldn't easily make 100miles, not to say that it wouldn't be a fun ev. If it did, you could get the same distance for a fraction of the price.
I could be wrong, but judging by TK's posts, I am assuming that ultimate efficiency isn't the primary goal here. If the Ranchero is a dream project, it's best to go that route and keep the motivation. If building the "ultimate" commuter EV was, I would suggest something like the Toyota.
...im ok with having something a little less like 50 miles or so and than later in life getting a better pack that weighs less and powers more just as long as i know its possible to achieve i basically ok with it.
White Zombie has proven that an old hot rod can get that type of range, with the right battery pack - so his goal is definitely possible.
 

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I contemplated the idea of building a commuter EV for a year or so but scrapped the idea due to cost for the performance I would get. I came back a year later with a different mind set and goals, my project is a toy, but it's a toy I could drive every day if I wanted to. From the new perspective the project is a bargain, but should provide all the fun I can handle. Sure there are lighter, "better" cars to conver than a 944 (2660lb curb (dry) and so/so drag) but why? I think you need to find the vehicle you WANT to drive then make it electric. I don't see the point of a $20k conversion in a car you don't want to drive, or might not want to drive in 10, 20, 30 years.

And like Todd said, throw in a big DC motor and enjoy it, the nice thing about electric cars is even if you have a really big motor, you can get V8 performance when you want it, but 4 cyl economy when you don't. (within reason of the car of course, there is no economy/efficiency penalty for the big motor other than a bit more weight)
 

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And like Todd said, throw in a big DC motor and enjoy it, the nice thing about electric cars is even if you have a really big motor, you can get V8 performance when you want it, but 4 cyl economy when you don't. (within reason of the car of course, there is no economy/efficiency penalty for the big motor other than a bit more weight)
That is such a good justification for having an 11" motor in my 350kg trike!:D
 
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