Thursday, July 24, 2008

The ICE is Melting

Over the last couple of days I removed the ICE components from the car. The first step was to drain the gas tank. There wasn't much to drain because I tried to use up all of the gas. I used the fuel pump to transfer the gas to this can and ended up getting about 2 gallons out.

Next I used the great engine removal procedure from the Pelican Parts tech articles. The transmission and engine are held in the car by 2 bolts at the engine and 2 bolts at the rear of the transmission. After disconnecting all of the cables, the gas lines, and the exhaust components it was a simple matter to unbolt the engine and transmission and lower them to a dolly on the ground. After that I separated the engine and transmission and here is the result.

I have the engine listed for sale in Craig's List. I hope it will be gone soon.

After I got the engine and transmission out the last thing to remove was the gas tank.

Here it is in the car.

And here it is out.

Now that the ICE components are all out of the car the conversion can begin in earnest. Next up is installing the controller.

But before I can do that I have to leave tomorrow for a week long business trip to China. Here's a preview of that.

This is the Great Wall which I visited on a previous trip.

Converion Parts

Before beginning the conversion I thought I would give you an idea of what it takes to convert a gas powered car to electric drive. Since the car will no longer be using gasoline to power it we need a different source of power. In this case the source is eighteen 8 volt flooded lead acid batteries. The battery voltage and quantity has been chosen to give a final output of 144 volts DC. Here are the batteries being stored while the conversion takes place.

The charger is connected to keep them at peak charge so no sulfation will take place. This battery charger is an intelligent one. It is programmed to provide the right charging curves for these batteries so that we can get maximum power and life span from them.

Now that we've seen the batteries let's take a look at the battery boxes. These will be where the batteries reside in the car. They are made of plastic with welded seams to resist and contain any acid spills. The box below will be installed in the former engine compartment and will hold 9 batteries.

This box will be installed in the front trunk and will hold 6 batteries. That small box on the front will hold the accessory battery which will provide the 12 volts DC that most of the standard systems need in the car.

And this is the rack that the box will sit on.

And this is the front trunk where this box will be installed.

This last box will mount in the former gas tank compartment and will hold 3 batteries.

And here is where this box will sit.

Now that we've seen how the energy will be stored let's take a look at how that energy will be used. Here's a picture of the motor.

This motor will replace the gasoline engine as the source of power to turn the wheels. It will use the adaptor below to mate to the existing transmission using the existing flywheel and clutch. It should provide a decent amount of torque to power the car.

And here is the existing transmission that I will use after fixing a few leaks.

One thing I haven't mentioned yet is how we drive a 3 phase AC motor from DC voltage. The controller accomplishes this trick.

The conltroller will be installed in the rear trunk.

It takes 144 volts DC in and produces a pulse width modulated 3 phase AC output. So it is sort of like 3 inverters linked together but it is actually much more complex than that. It takes a variable resistance controlled by the throttle cable and changes the width of the pulses to effectively vary the voltage output. This is similar to the way that a variable frequency drive works for controlling large motors. Both the motor and controller are made by Azure Dynamics which was formerly known as Solectria. They used to make the Solectria car. There are a few of these still around.

There are more parts to the conversion than this but these are the major components. Next up is to remove the ICE (Internal Combustion Engine) components.

Wednesday, July 23, 2008

Restoration Complete

After more than a year the restoration is finally complete. The next thing I did was to put the engine and transmission back in the car so I could drive it a little. I had done the suspension upgrades needed for the additional weight of the batteries while I was restoring the car. I also wanted to test the transmission since I had not previously driven it more than a few blocks. This was important to me because I didn't want to do the conversion and then have to work on the transmission.

It turns out that it's a good thing I did this. I found that the transmission leaks at almost all of the places it could leak. Nothing bad but it needs to be repaired. As far as shifting it is great. So all I need to do is replace the seals. I hope this won't be too bad.

After driving the car for about a month I have now taken all of the ICE parts back off and I am starting the conversion. The rest of this blog will chronicle that process.

Restoration Begins

After getting the car home I got the car running enough to get a state inspection since I couldn't register it in Texas without one. I was surprised to find that everything worked after some cleanup so after getting it registered I took everything off and out and sent it to the body shop for paint. That took much longer than I expected but when it was finished I was happy with the work. While that was going on I was cleaning, painting, and powder coating everything I had taken off. I took all of the upholstery items to a shop and had them redone at the same time.

About two years ago I went to an EV rally in Palo Alto. What stuck in my mind after that day was that all of the homebrew conversions I saw were ugly cars. These were all cars that I would be embarrassed to drive. I decided than that I would not have an EV that looked like those cars.

During the time that the restoration was going on I ordered the 914 AC kit from ElectroAutomotive. I'm glad I ordered it when I did. It took so long to get it that I would have been very upset if I had finished the restoration and was still waiting for parts.

After getting the car back from the body shop I spent many more months re-assembling everything. This turned out to be much more work than I expected but the results were worth it.

Getting a Donor Car

Well I have finally taken the next step and started the conversion for the 914 from gas to electric. I should probably give a little history since I am starting this blog somewhat late.

I first got the idea that I wanted an electric car about 2 years ago. When I started researching the subject I settled on a 914 to convert because it appeared to have the best opportunity for range. Range is my most important consideration since I have an 80 mile (roundtrip) commute and this is what I wanted an electric car for.

The donor car I chose was purchased on Ebay for $750.00. It probably sounds like this was a really bad car for so low a price but I got extremely lucky. The seller got it in a storage shed auction and had no keys so nothing was tested. My criteria was to get a car from California or Nevada because I thought that it would have the best chance of having only a little rust. It turns out that I was right and this car had almost none. Even though it had little rust it was in bad need of restoration as you can see in the pictures.

Next step is the restoration.