Friday, February 8, 2008

Going to disable alternator on Civic

Going to try a test, going to disable the alternator on our Civic, and put in a high capacity battery pack to see if we can get better mileage. We are thinking this might gain us 10% better mileage...

Wednesday, January 2, 2008

Got our motor/transmission back!

After being at the shop for the better part of half a year, we finally got our motor/transmission back! The shop was commissioned to make an adapter plate and adapter hub for us, but they were too busy to finish it, so we got the parts back. The work has been partially done, luckily for us they decided not to charge for the work that was done. Anyways, we can now get back to our conversion after a break of several months!

Friday, June 22, 2007

Installed lightweight 4.5 pound battery in BMW M3, replacing stock 50 pounder!

So, we've made a lightweight 4 pound starter battery for gas cars. Took us several prototypes before we got to our final working configuration. Issues like power, charging, casing, configuration, balancing, hookup terminals, etc, had to be figured out. But in the end, it was worth it! We've saved almost 45 pounds from the BMW M3. Notice the lack of a spare tire in the M3, there's run-flat tires and an air compressor instead, to save weight. The stock 3 series has a spare.

This is the battery we are replacing! Notice how much smaller it's going to be.


A size comparison versus the stock M3 battery. The battery in front is from the Scion xA, and was hooked up so that we wouldn't lose our settings from the car.


Installed battery. We needed to use a one foot extension cable because the stock positive clamp on the M3 wasn't flexible enough to reach the positive terminal of the battery.

Saturday, June 9, 2007

Adapter plate and motor hub adapter is being made!

So, last week, dropped off my manual transaxle and AC55 motor to Left Coast Electric to get the custom motor mount adapter and hub made! Met and talked to Reverend Gadget, and got to look around his workshop. Very interesting, and he seems busy with a lot of projects. Anyways he recommended going without the clutch, and leaving the car in second gear. I did some calculations for top speed, since my gut tells me top speed in second should be around 85mph at 10k RPM (the AC55 is rated for 8k RPM, but it can go higher):

10k RPM, 83mph
8k RPM, 67mph

Not as fast as I'd like, but decent enough. Now in third gear, assuming the car can spin at 10k RPM:

10k RPM, 121mph
8k RPM, 97mph

Much better! Anyways I used the below data for the stock tire size and gear ratios:

http://www.scionlife.com/forums/viewtopic.php?t=39360:
8.189 gear ratio for 2nd gear

http://www.1010tires.com/TireSizeCalculator.asp:
185/60R15
876.1 revs per mile

Wednesday, May 16, 2007

Short video of my conversion project

Some people made a short video of my conversion project for some film thing! I was pretty nervous and don't like the way I sound on it, but anyways, it was a pretty fun experience.


Tuesday, March 27, 2007

Makeshift battery holder using magnets

It was very hard to find holders for 18650 sized cells, so instead, I bought some neodynium magnets, and covered them with copper tape. Works perfect as a battery holder! Lets me make various "pack" configurations. Here's a 7S3P pack. The magnets are attracted to the alligator clips and the cell bodies. I think using magnets with tape must have more resistance than a spring battery holder, but I don't think it's gonna affect the test results that much, since I'm not doing high discharge tests. I can do single cell, max 8 amp discharge tests, don't have the necessary equipment to do more.

Testing AC55 fitment, it's gonna be tight!

So, made a foamboard/cardboard mock-up of the AC55 engine (without all the fins, and without the box sticking out the side, or the bottom "feet"). I think I made the diameter a few mm too short, but it appears that cutting the fins is enough to clear the drive axles! At worst, I'd maybe have to shave a few millimeters into the front casing of the AC55 engine, which seems like it will be ok, since it's pretty thick. As for the side to side clearance, the box in the back of the AC55 is just about touching the passenger side frame. Tight fit, hopefully this won't be an issue! I wonder if you can move that box somewhere else. I need a thin motor mount adapter, maybe 1.5 or so inches.


I wish the AC55 was just slightly smaller, it seems like a great motor, except for the size/weight issue. Size-wise, it's not THAT much bigger than the MES-DEA 200-250, about 1.5" of the diameter is the fins. It's about 100 pounds heavier though, at 235 pounds vs. 134 pounds.