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Hello. I'm about halfway through Fiero based conversion/rebuild here in Columbus, Ohio and thought it was about time to join the DIY forums and introduce myself.

The car is being rebuilt around a WarP 11 motor and Raptor 1200 amp controller, with considerable body lightening and body work. I am working on a hybrid Li / Pb AGM battery system which hopefully will provide 30-40 KWH (depending on how thick my wallet is). The intent is to maximize range while minimizing the cost of the battery system with a slight weight penalty over an all Li Ion pack.

The project is coming along pretty well thus far, other than for the long wait on getting my transmission/motor adaptor/coupler from Electro Automotive, which I am hoping they will ship to me this week. :confused:

I would love to hear from anyone else working on or who has converted a Pontiac Fiero, or a similar sports car (Toyota MR2, etc.).
 

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Hi there. I'm doing a Fiero conversion as well, a 1988, using the AC31 motor from HPG. I got my adapter from www.ev-solutions.net and they are working on a coupler for me using my clutch spline. I'll be using a 108 volt 100ah TS lithium pack, prices are getting so low I don't think it's worth bothering with lead any more in the long term. I'm interested in what body mods you're doing to lighten the vehicle.
 

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Hello, HighTech and JRP3. Thanks for the welcome. I will try to get some photos posted soon.

JRP3, I think you made a wise choice on the tranny adapter. I went with ElectroAutomotive's adapter because they appeared to have the experience (and a Fiero pattern), but they botched the first one they sent me (profile of plate and coupler both wrong), and after telling them about the problem a month ago I am still waiting for the replacement. They have now had my money for 6 months and I'm still waiting for my adapter/coupler. They said they would ship it last week but at this point I'll be happy if it ships this week (or even next).

Are you buying direct from thunder sky? You are right about going with Lithium in the long run, but for a 40-50 KWH pack now, it is still some big bucks.....like as much as the rest of the rest of the rebuild, roller, motor, controller and all. I'd like to keep the battery pack under $10,000. The hybrid pack allows me to test the design with only partial cash layout first on AGMs, then add KWH's later....and end up with 100-150 mile range.

I plan to run at 156V. I wanted to run higher voltage than that, but Cafe Electric was already quasi-out of business and other than the Zilla, the Raptor 1200 was the highest voltage, highest amp controller I could find, and it only takes up to 156V. Oh well, I think pushing my WarP above 170V or so without modifying the motor probably isn't a good idea anyway.

On body mods, the first thing I decided was that the rear deck is heavy (about 40 lbs.),and the 90% drop off behind the rear glass is an aerodynamic nightmare. Vacuum big time. So I am fabricating a new rear clip with a hatchback sloped geometry. Made out of carbon fiber and with polycarbonate rear "glass", I will save 30-50 pounds. The hood also, is unecessarily heavy (about 45 lbs.) and can be replaced with a carbon fiber hood for at least a 25-30 pound weight savings (the weight in a c-fiber hood is in the metal attachment plates/latches). The glass sunroof can be replaced with polycarbonate for a substantial weight savings: 1/4" glass weighs about 3.2 lbs. per sq. ft. The pop-up headlights create aero drag and the motors and pop-up assembly adds several pounds a piece. I'm replacing the rear trunk compartment sheet metal with a deeper, composite battery/trunk compartment; this saves about 10 pounds. My 16 lb. OEM flywheel gets replaced with an aluminum one that weighs about half that. Replacing OEM seats with racing seats saves about 20 lbs. per seat (OEMs are almost 40 per). Rotors and wheels may be replaced with Al/Mg alloy if my pockets are deep enough, that saves at least 10 lbs. per wheel/brake.

The battery boxes are composite set in Aluminum angle frames, epoxy coated to prevent galvanic corrosion....about 1/2 the weight of steel battery racks and uncorrodable. I'm thinking about the side glass and doors. There is possibility for weight savings there but also some complications.

Anyway, I figure I have saved almost 200 pounds above what you save just by pulling the ICE stuff. Somewhere I read the 2.8L V6 & acoutrements weighed about 350 lbs. , so I figure my car will weigh about 2000 lbs. pre battery pack. If I can limit my battery pack to 800 lbs. I am only 100 pounds over stock Fiero weight when its all said and done. That should be easy to achieve using Lithium.
 

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JRP3, I think you made a wise choice on the tranny adapter. I went with ElectroAutomotive's adapter because they appeared to have the experience (and a Fiero pattern), but they botched the first one they sent me (profile of plate and coupler both wrong), and after telling them about the problem a month ago I am still waiting for the replacement. They have now had my money for 6 months and I'm still waiting for my adapter/coupler. They said they would ship it last week but at this point I'll be happy if it ships this week (or even next).
Wow, that's too bad, ElectroAuto has been doing this for a while I would have thought they'd know what they are doing by now. Craig at ev-solutions has been working with me because he wasn't sure his S10 adapter would fit the Fiero, so after I sent him a tracing of my transmission face he sent me one to check before charging me a cent! I had to shave just a little off the part right near the CV output shaft, and the lower holes for the starter/flywheel cover are different but they aren't structural so it doesn't matter. He's building a clutchless coupler for me from my clutch hub that I sent him, and still hasn't charged me anything. I fully expect to pay but it seems to be the opposite of your experience.
Are you buying direct from thunder sky?
Sort of, I'm getting in on the group buy through www.poweredbydc.com who's getting them from Thundersky. He's charging 1.10 per Ah plus shipping and whatever tariffs are involved.
You are right about going with Lithium in the long run, but for a 40-50 KWH pack now, it is still some big bucks.....like as much as the rest of the rest of the rebuild, roller, motor, controller and all. I'd like to keep the battery pack under $10,000. The hybrid pack allows me to test the design with only partial cash layout first on AGMs, then add KWH's later....and end up with 100-150 mile range.

On body mods, the first thing I decided was that the rear deck is heavy (about 40 lbs.),and the 90% drop off behind the rear glass is an aerodynamic nightmare. Vacuum big time. So I am fabricating a new rear clip with a hatchback sloped geometry. Made out of carbon fiber and with polycarbonate rear "glass", I will save 30-50 pounds. The hood also, is unecessarily heavy (about 45 lbs.) and can be replaced with a carbon fiber hood for at least a 25-30 pound weight savings (the weight in a c-fiber hood is in the metal attachment plates/latches). The glass sunroof can be replaced with polycarbonate for a substantial weight savings: 1/4" glass weighs about 3.2 lbs. per sq. ft. The pop-up headlights create aero drag and the motors and pop-up assembly adds several pounds a piece. I'm replacing the rear trunk compartment sheet metal with a deeper, composite battery/trunk compartment; this saves about 10 pounds. My 16 lb. OEM flywheel gets replaced with an aluminum one that weighs about half that. Replacing OEM seats with racing seats saves about 20 lbs. per seat (OEMs are almost 40 per). Rotors and wheels may be replaced with Al/Mg alloy if my pockets are deep enough, that saves at least 10 lbs. per wheel/brake.

Anyway, I figure I have saved almost 200 pounds above what you save just by pulling the ICE stuff. Somewhere I read the 2.8L V6 & acoutrements weighed about 350 lbs. , so I figure my car will weigh about 2000 lbs. pre battery pack. If I can limit my battery pack to 800 lbs. I am only 100 pounds over stock Fiero weight when its all said and done. That should be easy to achieve using Lithium.
How much are you spending on carbon fiber and other body mods? Since the hood and trunk aren't structural you could use glass cloth instead of carbon and save some cash. While it's good to save weight I wonder if you'd be better off spending the same money on more lithium instead and skipping the lead batteries. You'll save more weight, plus unless you do a lot of stop and go driving the weight is less important than aerodynamics. Another thing, are you sure the chop back has poor aerodynamics? The reason I ask is that I've seen where pickup trucks with an uncovered bed created a "ball" of air in the bed which actually smoothed the air flowing over it. Just some thoughts.
 

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Discussion Starter #6
Yes, ElectroAuto has years of experience and from what I have read, good products, but they are SLOW!!!! It took about 10 weeks to get me the adapter the first time. It sat in the box for 2 months due to the feezing Dec.- Feb. cold, then when I could get out in the garage to hook it up, it didn't fit!!!!! It took ElectroAuto two weeks just to answer me what they were going to do about their mistake. I had to send them pictures of the gap between the adapter plate and the tranny bell housing and of the coupler too big to fit the flywheel before they finally agreed to do something about it. Then they said once they got it back they should be able to remachine it in a day or two and would ship it back to me 3 day express....that was more than two weeks ago they got it back.As far as I know it still hasn't shipped.

They still haven't explained how or why they screwed up in the first place. I told them it was a Muncie M-17, 4 speed transmission that was attached to the "85 Fiero's 2.8L V6, and sent them tracings of the tranny housing, clutch, and flywheel. The adapter plate definitely did not match the tracing I sent! (sent twice actually, they lost the first set of tracings I sent. hmmmm....) And they claim they have a pattern for this transmission adapter...that is why I chose them! My bell housing looks just like the pics in the GM '85 Fiero Service Manual.....nothing odd about it. I don't get it.

Is this the same transmission and engine as yours? If E.A. doesn't send me the adapter soon I may end up in the market for another adapter manufacturer. It sounds like I should try EV-Solutions; It seems I should have bought from them in the first place. Live and learn. Anyway, I'm glad it is not a $10,000 conversion kit I am waiting on! It bothered me that E.A. wanted payment in advance. The other EV dealers I dealt with billed me when the order shipped. KTA & EV of America were great!

I probably will use one layer of fiberglass and one of carbon fiber on the hood & rear clip. I got a good deal on C-fiber, about $30 per yd. so for the hood & rear its only a couple hundred $. If I used only f.g. I would need at least one additional ply and it still wouldn't be as strong. By the time you pay for the extra epoxy to do another layer its not that different.

The weight matters for 0-60 time though; got to keep up with Tesla you know. :) As for aero drag, the Fiero supposedly has a Cd= 0.35-0.37 (depending on rear wing - and whose data you trust) . Somewhere I saw wind tunnel modeling of it and the most significant turbulence was behind the rear glass. Pretty much laminar flow elsewhere until you got to the rear end. If you compare that modeling to a car with a "properly" sloped back, like a Porshe 911, you find the Porshe has laminar flow all the way down the back glass to the rear end....and a Cd= 0.28. The only major difference I can see is that big vortex behind the rear glass on the Fiero. Laminar flow is generally thought to promote low Cd. The effect you noted is not entirely unknown though; drag reducing riblets (on fighter jets and missiles) function by creating tiny vortices that reduce boundry layer interaction between air molecules and the surface, but they have to be fractions of a millimeter high to do this....larger and they produce the opposite effect.
 

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This sounds like an awesome conversion! Two thumbs up on the weight reduction. I used to own a Fiero, and I still miss it.

The year the Fiero was out the EPA rated it as having the lowest highway horsepower requirements of all the cars in its database. Yep, this implies it had the best aerodynamics of any car you could buy that year. Even though I had the iron duke and just a 4 speed, my highway mileage was easily mid-30's, and would top 40 mpg if I kept the speeds down. Another bit of Fiero trivia I read is it is one of the few cars where the rear wing would both produce downforce and improve the aerodynamics (not sure if that was true for the smaller wing, bigger wing, or both). Google on "Kammback Aerodynamics", a sudden truncation is not necessarily as bad aerodynamically as you might think. It would be fun if you got the car running first, tested the stock configuration, and then compared it to a hatchback design.
... the 90% drop off behind the rear glass is an aerodynamic nightmare. Vacuum big time. ...
 

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Is this the same transmission and engine as yours? If E.A. doesn't send me the adapter soon I may end up in the market for another adapter manufacturer. It sounds like I should try EV-Solutions; It seems I should have bought from them in the first place. Live and learn.
I've got the 4 cyl and the 5 speed, I think it's an Isuzu trans? I would think all the bolt patterns would be the same but I'm not sure. This is what my bolt pattern looks like:


I probably will use one layer of fiberglass and one of carbon fiber on the hood & rear clip. I got a good deal on C-fiber, about $30 per yd. so for the hood & rear its only a couple hundred $.
That's another two 100ah cells ;)
If I used only f.g. I would need at least one additional ply and it still wouldn't be as strong. By the time you pay for the extra epoxy to do another layer its not that different.
Well you could use polyester resin if you're not using carbon fiber and save even more, but if you've already got the cf you might as well use it.
 

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Discussion Starter #9
Thanks for the compliments DavidDymaxion. Yes, the Fiero Cd is not bad, and compared to the big heavy cars of its day, that had all the aerodynamic styling of a brick driving down the road, it was great, but it can still be improved. Fiero's Cd 0.35 compared to Porshe's Cd 0.28 is not so good, and wind tunnel models show a low pressure area behind the rear glass (fortunately, the glass is small). The idea of a Kammback is to truncate the ideal teardrop form at the boot end after the airflow has been "set" into laminar flow along the length of the car. It still causes some turbulence and a low pressure area behind the car, but is a good compromise between length, space, materials for the car and aerodynamic ideal.My hatchback will follow Kammback aero principles.

JRP3, your tranny bell housing profile looks the same as mine....at least too similar to see a difference without looking at them side by side....except what are those two "brackets" (outlined in red) sticking out? Mine doesn't have that.

The cost of another gallon of epoxy to layup an additional fiberglass layer makes it more like one additional 100 ah cell....if the cells only cost $100 a piece. I considered using Polyester resin, but it limits the type of foam you can lay up over (to the expensive kind). Also, I saw some data on tensile strength, modulus, elasticty, etc. , and the epoxy layups are significantly stronger than those done with polyester resin, with vinylester resin falling somewhere in between the two. Since I am using the same resin for the battery boxes, which has to hold 400-500 lbs. of batteries, strength matters. Since the car has no airbags, I would like the body to have some strength as well, so I went with epoxy.
 

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JRP3, your tranny bell housing profile looks the same as mine....at least too similar to see a difference without looking at them side by side....except what are those two "brackets" (outlined in red) sticking out? Mine doesn't have that.
Those brackets hold the shift cables, different transmissions use different brackets.
The cost of another gallon of epoxy to layup an additional fiberglass layer makes it more like one additional 100 ah cell....if the cells only cost $100 a piece. I considered using Polyester resin, but it limits the type of foam you can lay up over (to the expensive kind). Also, I saw some data on tensile strength, modulus, elasticty, etc. , and the epoxy layups are significantly stronger than those done with polyester resin, with vinylester resin falling somewhere in between the two. Since I am using the same resin for the battery boxes, which has to hold 400-500 lbs. of batteries, strength matters. Since the car has no airbags, I would like the body to have some strength as well, so I went with epoxy.
You are correct in what you say about epoxy vs polyester etc. but as I understand it Fieros get their strength from the body subframe and did pretty well in crash tests. I don't think the construction of the hood and trunk lid will add much to it. Not that I'm trying to discourage you in anyway, I just hate to see you weighed down with lead, it's so 19th century ;)
 

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...The idea of a Kammback is to truncate the ideal teardrop form at the boot end after the airflow has been "set" into laminar flow along the length of the car. It still causes some turbulence and a low pressure area behind the car, but is a good compromise between length, space, materials for the car and aerodynamic ideal...
Isn't that the basic premise behind the Toyota Prius and Honda Insight styling? In profile, they look a little like truncated teadrops - at least much more so than a regular two or three box passenger car design.
 

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Hey guys, love what I am reading about here! Would like to see some progress of the Fiero if you have any pictures.

One thing you haven't mentioned is a belly pan. They are something easily made and can be pretty light weight. It also adds some functionality of debree and water protection. You might also look at covering up any front openings like the turn signals, radiator, etc. I have made some plexi-glass turn signal covers for my car but I haven't installed them yet. I covered up the entire front radiator opening and have 1/2 of a belly pan installed on my car. Every little bit helps.

Again keep up the good work and keep us posted.
 

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JRP3, yes, I know you are right about the primary structural strength of the Fiero coming from the frame/chassis rather than the body panels. If it had not been that I am using the same material for the battery boxes, which are structural, I probably would have gone with a less expensive resin, at least vinylester resin, but since the quantities were not large I didn't want to mess around with ordering two separate materials. Also this way I can familiarize myself with the mixing ratio, drying time, temperature properties of one resin while vacuum bagging and heating it without having to learn the properties of two materials. Anyway, I'm a bit of a perfectionist and If I'm going to spend this much time and money on something I figure I may as well do it in the best way possible.

If I use a small AGM pack, about 40 Ah I can keep the weight around 325 lbs. If I add about 550 lbs. of Lithium ion pack to back that up I can have around a 41.0 KWH pack for under 900 lbs. Not too bad weight wise...but you're right that I could get about 20.0 KWH from that 325 pounds if it was Lithium rather than Pb acid. That would give me about 50 KWH total....almost Tesla like. :)

I have some connections in China. I may see what kind of deal I can get on LiFePO4 cells. I'd like to get it running soon though, so may still need AGMs first.
 

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Dunno if someone has posted this link yet but here's a nice Fiero EV build I've read: http://greenplanet3.org/ev/Home.html.

I loved my '84 Fiero - when I first moved out to the US in '88 I took over the last 6 months of a colleague's lease on his Fiero - it was a sweet drive. If I ever get my Miata done (and I can persuade the wife :)) I'd love to convert one of them.
 

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I need to take some more recent pictures. A lot has been accomplished since I took these pics, but anyway it is a start. Attached is a picture of the newly arrived (last summer) Fiero before any major work. One in the process of pulling the engine, and the front end in the process of removing the radiator, AC components, etc.

The finished looking cars are the result playing with ideas on the car's picture in a computer aided drawing program. The bubble back one looks a little like an RX7 and the other has a real muscle car look, which wasn't exactly what I had envisioned.

I may do a 3D model in clay or foam before I execute the new rear clip in full scale.
 

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Thanks for posting the pics! That's awesome seeing someone actually working to improve the aero drag.

I'll admit I don't have a good feel for it, but what is the optimal angle for the rear to slope down? The Prius (one of the few cars designed for good aerodynamics) has an amazingly flat rear window. http://www.toyota.com/sem/prius.html?cid=Google_prius , as does the new Insight http://automobiles.honda.com/2010-insight/?ef_id=1097:3:s_c27375bf3f81190e82ede0dd0c1284d8_3270320864:oaJHvNBkOIYAAHPooHIAAAAJ:20090426222003#// .

I need to take some more recent pictures. A lot has been accomplished since I took these pics, but anyway it is a start. Attached is a picture of the newly arrived (last summer) Fiero before any major work. One in the process of pulling the engine, and the front end in the process of removing the radiator, AC components, etc.

The finished looking cars are the result playing with ideas on the car's picture in a computer aided drawing program. The bubble back one looks a little like an RX7 and the other has a real muscle car look, which wasn't exactly what I had envisioned.

I may do a 3D model in clay or foam before I execute the new rear clip in full scale.
 

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Discussion Starter #20 (Edited)
Yes, the Pennock's Fiero Forum is a good resource.

Apparently, according to the aerodynamicists around a 10° slope down the rear glass, boot end is ideal.

I was excited to get my transmission adapter back from Electroautomotive yesterday....until I saw it. As you recall they botched the first one. After sending it back and waiting 5 weeks I was hoping when it returned everything would go smoothly. No such luck. I removed the coupler hub from the package, fit it to the flywheel; it seems to fit this time. So far so good.

Then I removed the adapter plate and compared it to my tracing of the transmission housing. Unbelievably, it is wrong for the second time! :eek: The profile is nothing like the transmission housing tracing (two sets) I had mailed to Electroautomotive. See the attached picture.

Anyway, I spent my lunch break today looking for an aluminum plate supplier and a machine shop to cut and machine the plate. The one shop I stopped into thought it would be about $300 to cut the profile and drill the holes and another $300 to CNC the channel for the circular motor mount plate to set into. It sounds a little high just for the plate, but then it is a one-off job.

Post Script:
Ooops! Partly my mistake. It is not as bad as it looks. If you place the adapter plate on the back of the tracing the bolt holes line up. The only problem is a half inch gap near where the axle goes into the transmission. That point is not structural though, so perhaps it can be filled with calk something.
 

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