I also decided to use aluminum instead of steel to save weight (Steel is 3x heavier than Aluminum), I estimate that this will save me about 70 lbs.

The downside of using Aluminum is that the material is much harder to weld than steel, however, depending on the type and the treatment on the aluminum, it has better resistance to acid spills from the batteries. We started with the front compartment 5-battery rack and designed the rack using rivets.

To repair the damaged rubber in the original engine mounts, I found a guy that sold these molded urethane inserts for $50.

I also spray painted the mounts.

And mounted the transmission back into the engine bay.

That takes care of 3 of the 4 mounts, next I move on to making the 4th custom mount for the motor.

I then went on to make sure that the path is clear for me to drop the assembly in. It became clear that I needed to remove a few more things. First thing I noticed was that the front and rear mounts are really rusty, so I removed them and sprayed painted them after my friend Steve sandblasted them for me to get the old paint and rust off. It was then I noticed that the rubber inside the mounting bracket was cracked and must be replaced…

I removed the exhaust mounts (might be able to use them for mounting batteries where the exhaust system used to be…

Removed remnants of the fuel and radiator systems…

Top view of the transmission/motor bay… looks like the old 12V battery stand needs to go too…

I tried to drop the assembly in from the top, but the opening is too small…

From the bottom worked!!!

Use a level to make sure the motor is level, since the motor side is not mounted yet, I’ll temporarily use the hoist to hold it in place.

With the assembly in place, my next tasks are to:

1. Design the motor mount
2. Make some mock up batteries to layout the placement of the 20 6V flooded lead acid batteries

I also noticed that the adapter plate wasn’t cut by Electro Auto exactly to the needed shape, note the area marked with green marker that I will need to cut out to allow the clutch cylinder to fit on top of the transmission.

By the way, now that I have the assembly in the car, I decided to sell the old engine related parts. I posted an ad on craigslist and within a week, most parts were gone! My profit, $150, so my net cost on the car, not counting all the ev components, is $730 – $150 = $580.

The plate is bolted to the motor using the supplied bolts, and the key is inserted into the slot on the motor shaft. Note this motor has 2 shafts, the larger one is the one for the motor, I might be able to use the 2nd auxiliary shaft for the air conditioning system.

The hub is then slid over the shaft and key and finger tightened down such that the hub can still slide on the shaft with some force. This is because we will need to adjust where the hub is on the shaft once the flywheel is in place.

Next the flywheel is temporarily bolted to the hub using the original screws. Note, I had the ring gear removed from the flywheel and the flywheel lightened and balanced with the new pressure plate that I purchased. The ring gear is not needed on an electric system and just adds extra weight to degrade performance. I used Ashland Grinding and Balancing in Hayward. Mike, who owns the shop does really good work; he stays busy doing work on high performance cars like the Ferrari for his customers. My flywheel lost about 5 lbs from 15 to 10.

To properly fit the adaptor to the transmission, the distance from the surface of the transmission side of the flywheel must be 1.617+/- 0.005 inches from the surface of the adapter plate facing the transmission. This took a little while to get perfect, but I finally got it done! Next, we need to remove the flywheel from the assembly without moving anything and disturbing this distance. After successfully removing the flywheel, tightened the small bolts to secure the hub to the shaft.

Now bolt the flywheel back to the hub with a torque wrench to specifications based on the bolt size, then bolt the new pressure plate to the flywheel with the new clutch disc sandwiched in the middle. Note the alignment tool used to center the clutch disc along the shaft of the motor. Note also to use a cross pattern when tightening the bolts so that we don’t create an off-center fit.

Time to hoist the transmission to the motor!!

The transmission was aligned to the engine using 2 10mm steel dowel pins, I tried to remove them from the engine but was not successful but I did find replacements at McMasterCarr. I love that place! You can find the almost any thing you want there. The first 2 shots below are marked with the location of the alignment holes on the adapter plate and the transmission. The alignment holes on the adapter place was too tight, so I had to sand down one side of the dowel pin a bit and used a lubricant to help drive the pin into the adapter plate. Make sure you drive this pin straight!! Also, make sure that you protect the motor from metal shavings by wrapping a plastic bag over the motor.

Since the engine has been replaced by the adapter plate and motor, I had to source the bolts and nuts of the right dimensions necessary to mate the motor to the adapter plate from the local Kragens auto parts store. I used grade 8 (class 10.9) bolts where possible. Also, the rust on the mounting brackets were bothering me, so I cleaned them up and spray painted them with a nice coat of Rustoleum, shiny!!!!

After struggling for a bit to mate the transmission to the adapter, I finally got it together! The trick to was to remove the passenger side differential connector to the wheel shaft. When this was removed, transmission fluid leaks out, so be ready with a bucket!

• Motor to transmission adapter plate. EVA offered a clutchless design but I preferred a clutch design. I ordered my adapter from KTA services. As I found out later, they source the adapter from Electro Automotive.
• Manzanita Micro PFC charger. This charger has variable input and ouput, which will allow me to try out different battery packs with different voltages easily. I found one for slightly cheaper than a brand new one on craigslist.
• I am still missing a vacuum pump for the braking system and a battery gauge (the battery gauge was back ordered and subsequently discontinued by the manufacturer and the vacuum pump will be purchased later). EVA has these parts, so I will likely order from them shortly in the future.

The parts all arrived shortly after the 1st of the new year.

It would have been great if we could have made it with Steve’s EV during our test run, which would mean that I could just copy exactly what Steve did. However, it looks like I will definitely need more battery capacity. Here’s some back of the envelope calculations that I did. Steve’s 15 8V battery system is about 20.4 kwh and has a practical freeway range of about 30-40miles, based on our test run. If I can fit 20 6V batteries, each of which has about 40% more capacity (US Battery 125 XC):

• 20 * 6V * 242 amp-hours = 29.04kwh
• 29.04 kwh / 250 wh per mile = 116 miles
• 116 * 50% = 58 miles

Looks like it might work, at least on paper. Just as I was contemplating how to go about getting 20 6V flooded lead acid batteries (dimensions of each battery: 10.25L x 7.125W x 11.25H) in the MR2, I met Doug Coleman at one of our recent EV club meetings in Alameda. He brought his recently converted MR2 with just that configuration. I even got a test ride in it.

Decided on my new path, I will start sourcing parts for a DC system assuming a 120V flooded lead acid battery pack.

• 15 8V flooded lead acid (US Battery 8VGC XC)= 120V
• Curb weight: 2700 lbs
• 8″ Advance DC motor
• Webpage: http://www.evalbum.com/853

The 8VGC has 170 amp-hours of capacity each, which comes out to 20400 watt-hours (170 amp-hours * 8V * 15 batteries). A rough estimate I got from online EV conversion resources is that it takes about 200-250 watt-hours to go a mile, depending on terrain, speed, weight of car, aerodynamics, tire resistance, etc. Since the commute will be mostly freeway at 65mph, I used the 250 wh/mile as a conservative estimate. So if we completely drain Steve’s batteries, we could theoretically go 81.6 miles. However, draining a battery too much will adversely affect the life of the battery, the performance also suffers when they are drained. Most EV resources recommend that one does not drain lead acid batteries below 50% depth of charge on a regular basis. Therefore, Steve’s car can practically go around 40 miles or so at freeway speeds. We knew it was going to be a challenging test run to go 44 miles but wanted to try anyway. I rented a small generator just in case we needed to charge mid-way.

We made it to work with no problems and started on our return trip, with about 10miles left, we noticed that the battery was starting to tire and decided to stop and get some coffee and charge the batteries a bit. Well, the coffee was good, but the charging didn’t turn out too well since the small generator I rented was too weak to drive amps into the battery. Nervously, we started our last 10 miles back to Castro Valley. Instead of taking the freeway, we opted to take the back roads at slower speeds for obvious reasons. Though we made it back to Castro Valley, it was really close and we almost didn’t make it, we didn’t even bother going up the 9% grade hilll back to my house since towards the end, the car struggled on take off and small hills. I felt really bad that the small generator I rented didn’t work and that the test run might have damaged Steve’s batteries but am glad we made it back to Castro Valley at least. When Steve got back to his house, he had about 40% left on his batteries.

Per suggestion from Tim Kutscha (He is heading up an open-source civic EV project: VERY HELPFUL SITE), I cleaned the transmission with Simple Green Max the best I could without getting moisture into the bearings.

The clutch assembly is mounted to the engine.

After removing the clutch cover, the worn out clutch disc was removed. The clutch disc pads were worned down to metal. No wonder I couldn’t make it up that hill when I first got the car!

Here’s a shot of the new clutch parts that I ordered that will replace the old clutch assembly (from left to right: clutch bearing, clutch disc, clutch cover):

Compare the worn clutch disc to the brand new one here:

After removing the clutch assembly, I removed the fly wheel from the engine:

The fly wheel weighs 15 lbs.