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Discussion Starter · #1 ·
I'm looking for a car to convert to run off electric and I need some data on the Opel GT that I haven't been able to find, to see if it would be a suitable choice.

I have the curb weight, gear ratios, and rim sizes.

I do need, however, the following information:


What is the drag coefficient of the vehicle?

What is the frontal area of the vehicle?

Do you happen to have the gross vehicle weight rating? How about for front and rear?

Dry weight of the vehicle?

What is the approxamate weight of the engine?

Weight of gas tank and fuel feed systems?

Weight of the exhaust systems?

Any idea on the amount of space within the engine area and the trunk area? Dimensions?


Also, what sorts of suspension upgrades could I use if I wanted to increase the maximum gross vehicle weight rating? Are there any particular leaf spring sizes I'd need?


My intent is to cheaply build an electric vehicle that gets 0-60 MPH ~7 seconds, tops out at around 120, 1/4 mile in high 15 seconds or less, does approxamately 80 miles per charge at a steady highway speed(Or 120-ish on a cycle drive), and can handle at least as well as the .83g it attained on a 216 foot skidpad back in '73, preferably better though. This would entail using 20 Evercell MB80 nickel zinc batteries 12V nominal weighing at 50.2 lbs each all wired in series(For a total of 1004 lbs. of batteries and 240 volts), a DCP Raptor 600 controller that's 18 lbs, and an ADC 9-inch series wound motor weighing in at 143 lbs. Add in about 400 pounds for driver, adaptor plate, wires, fuses, ect.


In order for this car to be suitable, I will need to keep final curb weight below 2,700 lbs and I'm looking for an overall Cd.A of less than 5.5(Coefficient drag times frontal area in square feet).

The Evercells have a power density of 280 watts per kilogram, meaning, I'd be able to push about 170 horsepower maximum through the motor(Not constantly though, I'd damage the batteries if they were nickel zinc.). The torque from start up would be able to smoke tires, so I'd probably need a different tranny and drive axel so I don't break anything. But lets say the car weighs 2,700 pounds. That's a power to weight ratio of .063, which given that electric vehicles produce peak torque from start, this would be well capable of impressive acceleration, easily in that target I'm looking for. The aerodynamics are a huge factor in energy consumption and acceleration past 40 mph, thus they are also important. I'd want to place as many batteries as possible towards the center of the car, usually behind the driver's seat, to keep the weight balanced and to keep the center of gravity as low as possible to nail the car to the ground.

All in all, this would cost me about $10,000.

If this car can meet my needs, I'll be buying one in the near future. If not, I'll keep looking somewhere else.

This is intended to be a starter project, at least until I'm able to build a car from the ground up.

Thanks.
 

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did you consider a porsche 914? i have seen this done to them very nicely. lots of room out back, and up front.
 

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Discussion Starter · #3 ·
I have, and it would make a great conversion.

But I'm curious to see how the GT would compare.

That, and the 914 is rather fugly.

I have considered using a 914 frame and building a custom body onto it later though, but I really like the idea of an Opel GT. That thing just looks so slick...

I've also considered using lead acid batteries instead of Nickel Zinc batteries for this idea. Optimas, specifically, and a high current 1000 amp controller. Only problem is that this would halve my range and cost nearly twice as much. But it would certainly perform. 1/4 mile in under 13 s would be my guess as of now.
 

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Discussion Starter · #4 ·
Well, given the amount of views this has gotten, I guess this data isn't published.

I tried guessing the frontal area through takeing the legnth and width and multiplying it and then multiplying that result by .83. Problem is, on google while I was searching for the car's frontal area, I came across a forum where someone said the frontal area was 15 feet square, but there was no source. This is three and a half square feet lower than what I calculated through the length and width and multiplying it by that constant, which is roughly 5-10% accurate for every other car I've found.

As for the drag coeficient, that same post in that other forum said .39, but then again, don't know for sure. The car seems sleeker than that.

Eventually, if I do an electric Opel GT, I'd use a fiberglass hood and front body piece along with fiberglass doors to lighten the car perhaps an extra 150-200 pounds. Maybe even build carbon fiber body pieces instead, if they aren't available. The wheel wells would be covered, much like the electric GT that Opel built in the 70s to reduce coefficient of drag by about 15%.

Add to that a rear window that can hatch open, much like the trunk on the Audi TT.

I'd want a forest green paint sheme with a big black stripe going down the center of the car from front to back.

All in all, this would turn out really nicely. Then when I get another $20,000 after first building this, I can work on adding Lithium Ion batteries and an AC drive system, but we can all dream on, can't we? ;)
 

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Discussion Starter · #5 ·
Well, I guess that info just isn't around. Quite a shame. This looks like it could make a good car.

As for that electric 914 someone mentioned, you may want to watch the following videos if you want to know what electric cars can do:

Little Burnout for fun and heating the tires properly for the strip:

http://www.nedra.com/movies/pso04/OtmarsBurnout1.mov

13.8 second 1/4 mile drag vs. electric Nissan:

http://www.nedra.com/movies/pso04/CAPOPE_vs_Silver_Bullet.mov


I can just imagine a GT pictured in that video instead. Wouldn't that be lovely? Or better yet, at an autocross... *drool*
 

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Discussion Starter · #7 ·
Thanks for that link. Never used boards like these before.

Well, I found the GVWR, so I will really need to beef the suspension up if I want it to handle the weight.

My estimate is that it will weigh 2,900 lbs. Assuming I have room for batteries and what not, this car, even though weight and aerodynamics couldn't meet my goals, will still be able to do what I want.

I calculated the following:

*170.1 peak horsepower
*236 lb-ft peak torque at 0 RPM (Tire-smoking fun!)
*Onboard specific energy at 100% charge = 20.4 kWh
*Upper estimate of range on highway @60 MPH = 87 miles per charge
*Lower estimate of range on highway @60 MPH = 75 miles per charge
*Upper estimate cycle range @80% depth of discharge = 84 miles
*Lower estimate cycle range @80% depth of discharge = 79 miles
*Highway energy consumption around 250 wh/mile, or factoring in powerplant and charging innefficiencies, a well to wheel energy efficiency of 40 miles per gallon equivalent total energy use
*City energy consumprion around 190 wh/mile, or a well to wheel efficiency of 53 miles per gallon equivalent total energy use
*Combined energy consumption around 220 wh/mile, or a well to wheel efficiency of 46 miles per gallon
*Best estimate 0-60 MPH = 6.6 seconds
*Worst estimate 0-60 MPH = 7.5 seconds
*Best estimate 1/4 mile = 14.7 [email protected] MPH
*Worst estimate 1/4 mile = 15.9 [email protected] MPH
*Top speed = 123 mph

All for a total cost between $9,500 and $13,000, depending on where I shop and what I can scrounge used.

Better yet, if I was rich, I would be using some ultra capacitors and boost my ponies well into the 220 range. THAT would be a sight to behold! One can only imagine...

The main iffy thing though would have to be the handling. Unless I have enough room to sink the batteries into the floor just behind the driver seat, the handling will get really bad. I want it to be at least as good as the original, and most electrics tend to be better with a lower center of gravity.

Again, thanks for the help. If I begin this project, I'll let you guys know. This would be one sweet ride.
 

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I have been doing Battery research for the range and such..

So far the best bet I have is the

Discovery Battery - EVGC8A-A
8V - running 18 (144V) wieght of 1152
8V - running 15 (120V) wieght of 959

Batterys are 10.2" x 7.1"

Amp hours are in the 175 range.

Motor I am looking at is a TransWarp11 shoudl smoke the tires..

Hoping to have a final curb wieght in the 3000 range on a Manta.

Charles
 

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Electric Vehicle Info

For those that might have interest in going electric.

Try Here
 

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Egt

I saw one converted on ebay 3 or 4 years ago. I think it was out west somewhere but not sure. Maybe someone will remember this:lmao:
 

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Opel Tinkerer and Rescuer
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Done a lot of work and research on this..

http://www.go-ev.com/

The WARP9 is the motor I have decided on.. built for EV conversions.. and one of the best built as well. Its also the best bang for the buck..

I am getting it and most my components from
https://www.electricvehiclesusa.com

Café Electric Home of the Zilla

The motor controller I picked was the Zilla 1K

Power-Sonic

The Power sonic batteries are using the technology first used in the first GM EV1, and are better suited for EV use, and are cheaper than the NiCAD or LiIon alternatives.. They are also smaller than similar flooded lead batteries, and Automotive style of batteries.

I am also going with a clutchless design,using a T-5 transmission. For Manual tranmission cars, you can simply use the T-5 like those that converted from the 4 spped to T5. For cars like my Automatic converting to clutchless saves you the problem of modifying the firewall.

Find attached my research and calculators..

A great calculator for EV conversions is:

EV Calculator

Find attached all my calculations for my Manta conversion..

Looks like I will have a 40 mile or so range, 0-60 in about 8 sec, top speed of 90 mph or more.. so real world performance, and range enough to get to work and back.

The trick with my conversion over those I have found is the ZIlla controller. Many will say you have to match the Voltage of the pack to the motor. But that is NOT true of the Zilla. Why this is important, is you can add more batteries and go up on voltage. If you try to stick to the voltage limit of the motor, the AMP Hour rating of the batteries becomes a limiting factor.. along with thier wieght. If you have the ability to just add 2-3 batteries and up voltage but stay with the same AMP Hour you get more power for a longer range without having to sacrifice wieght.

As far a I know, the Zilla is the ONLY controller that allows you to have a higher voltage than the battery pack and then the controller trims the voltage to the motor. It will drop voltage when cruising to add extra range. Other controllers modulate the amperage only. It took me a while to understand the differences and affects to the battery pack.. and I still dont completely understand it. I hope once I am in the construction phase of ths system I will get a better grip on it all.

New techologies in the Zilla, and batteries, and chargers, etc.. will give you a lot of different opinions as you talk to different people doing conversions. Most are stuck in old school designs and logic and say things like I am done will not work. That said, the system I am doing I know will work..

Thats because the guys at Net-Gain (www.go-ev.com) that make the motors told me to go to Cafe Electric and talk to the guys making the Zilla controller, and I called and talked to tech support at Power Sonic for batteries. They all know thier products and have talked to a guy that has built a similar system.

So I guess what I am saying its important to get information from many sources. And try to use your best judgement to figure it all out. Most of all dont take everything I have done and take as gospel either.. because you may come up with a different solution or opinon as well. All the research I did took about 2 months.. I am still not done as I am on the wating list for my controller and motor and havent started perpping the body for the batteries. I hope to have my project done by 2010.

Hope this helps you and any other Opel EV'ers

Charles
 

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Opel Tinkerer and Rescuer
Joined
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7,517 Posts
I have been doing Battery research for the range and such..

So far the best bet I have is the

Discovery Battery - EVGC8A-A
8V - running 18 (144V) wieght of 1152
8V - running 15 (120V) wieght of 959

Batterys are 10.2" x 7.1"

Amp hours are in the 175 range.

Motor I am looking at is a TransWarp11 shoudl smoke the tires..

Hoping to have a final curb wieght in the 3000 range on a Manta.

Charles

Wieght and voltage were limiting.. and when I finally did a full check on charging solutions, cost, range, wieght, etc.. the numbers didnt work out..


See post above..
 
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