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Discussion Starter #1 (Edited)
Hi,

Newbie here trying to read through all of this great information and folks' contributions. I am an MBA / IT network guy that does a little ICE maintenance work, does not know EE math, and is new to CA (relo from Pacific NW). I have a bunch of tools, but not sure they are the right ones, but will buy them if necessary. I could really use a coach / mentor to help me navigate the math, products etc (I know...who doesn't [email protected])

1988 Pontiac Fiero (4cyl) Automatic (ugh)

Initial Goals:
Commute to work (25mi) each way (office has charging station in back!)
Accelerate to 65mph (highway speeds, bumper to bumper traffic, merging etc)
2 Passengers (400lbs combined)
Location: San Jose, CA
Budget: 4-6K
Time: Before wife gets sick of nothing getting done!

Optimal goals: +$8K?
100mi distance before charge
0-60 in 5sec (please?!) ;-)
Regenerative braking

I've been thinking about a 144v (240v??) motor (not sure which one yet, don't get volts-HP equivalency) and LiPo battery packs. I've found 72v100ah med discharge batteries that I like (working on the price). Not sure how many I need at this point (initial or optimal). Also, having worked at Boeing for a number of years, I've become a little enamored with the idea of using a 777 electric starter motor...any guesses why?? LOL (can someone talk me out of this?)

Things that I've been considering:
Dropping the automatic transmission and replacing it with ????
- Would like to have mid-engine tranny that is fast off the line but an over-drive for highway.
- May go with paddle shifters instead of clutch, wifey can't drive a clutch and has no desire to learn... (suggestions?)
Not using the Fiero but a tubular body (Fiero was $400 and barely running) but no accidents and disc brakes!

Thanks again for your thoughts, links, lessons learned etc. Anyone in the area that I can connect with and compare notes? I live in the Campbell area.

Thomas
 

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> 0-60 in 5sec (please?!)


It is not possible in your budget
You should hope that you will get acceleration like running ICE
 

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Discussion Starter #4
Thanks for the reality check(s). I was trying to be a little bit humorous.

Metric, your build is very close to what I am interested in tinkering around with. I don't have 'race dreams' however, I am interested in having some get up and go to make the morning commute a little more interesting. I have charging power at work so I can keep a full charge at nearly all times.

I'm very interested in your LiPo pack configuration and your thoughts on leveraging the front end (under the hood) of the Fiero. Your use of space for the dual Warp 9s is very inspiring and I would like to incorporate that idea into my 'phased approach' to building up this EV.

Do you have any recommendations for a transmission? I'm thinking that I will be taking this out onto the highway/freeway for my commute and would like to have an overdrive capability along with a fast first & second gear. I was thinking about the Corvette C5 or Z06 6-speed transmission, but is there a cheaper easier option? My wife can't / won't drive a manual so I was thinking about leveraging their paddle shifters.

I really appreciate your leadership you've taken in this space and thanks again for your links and documentation.
 

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I'm very interested in your LiPo pack configuration and your thoughts on leveraging the front end (under the hood) of the Fiero. Your use of space for the dual Warp 9s is very inspiring and I would like to incorporate that idea into my 'phased approach' to building up this EV.

Do you have any recommendations for a transmission? I'm thinking that I will be taking this out onto the highway/freeway for my commute and would like to have an overdrive capability along with a fast first & second gear. I was thinking about the Corvette C5 or Z06 6-speed transmission, but is there a cheaper easier option? My wife can't / won't drive a manual so I was thinking about leveraging their paddle shifters.
Well the transmission tunnel approach is not really expensive but requires a lot of sheet metal bending and cutting and welding skill.
You could put a motor and TH400 transmission in the front of the car, but again you would be fabbing up a lot of custom motor mounts and really taking a sawsall to the unibody and rewelding the strength back in.
For a daily commuter I would start by scanning through EVALBUM.COM and search on Fiero. There must be a hundred in there. Look for builds that give the same performance you are looking for.

With twin Warp9's I don't think you need the gear vendors overdrive. I don't even kick mine in until about 70mph. However, with a single Warp9 or Warp11 you may consider it. You may want to consider a large Warp11 into the stock Fiero Transaxle with a lenco gear reducer flipped around to make a permanent overdrive. This would give peak power around 5000rpm, be a reasonable 300ftlbs of peak torque and be able to run all the standard transaxle transmission functions.(This is a new idea I am afraid but I think quite doable.

I would stay away from the LiPo's for daily driver. The claimed cycles on them is around 300. I am near 180 but that race driven cycles. I am afraid fi you drove every day and the cycle life truly is only 300 that you would be replacing a pack a year. I will let you know more when I pass 300 cycles if they have more due to proper balance and management.

John Metric
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hey there, i'm restoring/converting a fiero (a project that has taken way too long due to lack of money and time) and i'm afraid that your goals of 4-6k will not get you the performance you want. you would be looking at used forklift parts (hopefully for free or next to nothing) and used EV stuff you can find online. but if you look around you can get some good stuff for around 8k.

my suggestions are that you run a 144v system and get a 9 inch motor...i know your wife doesn't care to drive stick...but ev's are not like normal stick...you don't have to balance both pedals to keep it from stalling and there isn't much shifting anyway with an electric car. and you don't need overdrive because evs are more efficient at higher revs

and then there is the topic of batteries...since you only need 25-30 miles, lithium is affordable for your application, lead would add lots of un-wanted weight which would hurt performance and range and would only last a few years

with a 144v system...a 9 inch motor...and possibly lithium batteries...it will perform nicely
 

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Discussion Starter #7
E-85

Thank you very much for your encouragement and support. So at 144V and my range, how would I calculate my AH for LiPo batteries?

Of course, I'd like the answer, but if someone could help me with the formula then I can make adjustments to my calcs later on.

For LiPo batteries, is it a linear line for distance calculations?

50AH = 10mi
100AH = 20mi
etc.

TIA
 

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there are formulas to figure all that out...and i have in the past but don't know what the formula is right now. anyone know where he can find it?

but the thing i found most helpful was real world performance reports from other EV'ers. i looked through build threads, evalbum, and battery performance threads on here too. judging by results cars were getting with different batteries and controllers...compare weight...you can find similar projects and model your build off another car...but make changes where you feel you need to.
 

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Don't use lipo, use lifep04 batteries. Much longer cycle life.

In regards to range it depends on => what speed you are driving, weight of car, aerodynamics, what tires, altitude, driver's lead foot etc etc.

Having said that two rough rules of thumb is ICE mpg * 8.5 gives you your watt hours per mile. And that a very small car is 200, medium 250 and large 300 watt hours per mile (wh/mile).

So if your was 275 wh/mile to go 30 miles you need.

250 * 30 * 1.2 (DOD) = 10 kwH

10 kWh at 144 volts is (46 batteries @ 3.2 volts each) 10000 / 147.2 = ~70 ah
 

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Discussion Starter #10
Ok, this is all very helpful. In the above post I noticed that there is a reference to 3.2V batteries. However, the amps were not listed. In looking around for batteries I have run across everything from 1800mA to 3.0A.

At this point, if I was able to put ~200AH of batteries in my car then I would be able to get 70-90 miles range out of it.

Any suggestion on which 3.2V batteries I should be looking at?
 

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ya i have been really looking into the sinopoly cells...the new 200ah cells are lighter thinner and have a much better energy density...its the best bang for your buck right now...about $220 a cell from china. i plan on ordering as soon as i know my house is sold, and that will get you the range you want and maybe more...this article (not sure where i recently posted this link, haha maybe earlier in this thread) but she used 200ah ThunderSky cells, and the new Sinopoly are a superior cell. like i said, lighter with better energy density, you should get better performance out of them then the older TS 200. and her miata is very similar to our fieros...hers is lighter...fiero 2590lbs and miata 2150lbs... but ours has better drag coefficient the fiero with 3.2 and the miata with 3.8. who knows how much weight she removed with the ice stuff, but i dropped alot fo weight and my Sinopoly cells will be lighter then hers.

http://www.elitepowersolutions.com/electric_vehicle.html
 

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Discussion Starter #12
Ok, just brain-storming here.

What would be your opinion of having all four wheels powered. I'm looking at:
http://www.evlithium.com/html/High_Power_Motor/111.html

Each wheel has a maximum speed of 44mph @ 1300 rpm. What I am curious about is if this is constrained by heat from the motor or the actual rpm. If I had all four wheels powered by these would my max rpm still be 1300 or would I be able to take 50% gain from the other wheels due to the reduction in energy draw for each one?

This doesn't seem right to me, but I'm not sure where the flaw in my logic is. For this kind of application I would like to have a max speed of 70mph and 40mi range.

Thoughts or feedback?

Thanks in advance.
 

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maybe somone else would know more...to me it seems a lot more complicated...do you need different knuckles at each wheel, with it work with stock spindals up front, and hubs in back? you may drop the drivetrain but how much will you have to modify to get those to work on the car...i'm not sure about the rpm and what you could get away with on those wheel motors, but another question is are you going to have to get a controller for each one?
 

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Discussion Starter #14
I had considered all 4 wheels being electrified, but upon considering your comment, I would also consider just the rear wheels. The motors are 110V ea so I could probably get a 220-240V controller to wire both of them. The trick, I believe I read somewhere, is to make sure the leads are exactly the same length to each motor. The interesting part is that it may remove the need or requirement for a transmission and may just make it a high-speed golf cart. With good airflow to cool things off it may not be a problem.
 

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if they can power the rear wheels with little modification then it might be worth it, but they might not be efficient without a transmission. i don't know i'm just throwing stuff out there...maybe try and find someone who has used this set up in their vehicle. with most ev's you just put it in second and drive around town, and to drive on the highway, pop it into 3rd...with no tranny i don't know if those motors could bring you to highway speeds, or if it could do it efficiently...anyone know much about these wheel motors?
 
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