Tuesday, September 15, 2009

September Update - ITS ALIVE!!!

The big news for this month is.... The car is on the road!!! Or rather I guess I should say that the car has been on the road. When I initially was planning for this conversion, I wanted a 4 wheel drive car so I sized the motors accordingly. Right now, I only have the rear motors installed (still haven't figured out how to get motors on the front wheels yet). This means that I only have half power and since I went with direct drive, I'm having some issues with hill climbing power. As for straight out flat speed, I've had the car up to 62 MPH (my goal was for 65) so I am right on track there. But when I try to drive the car back up our driveway, which is VERY steep, I can only make it up about 20% of the time. I'm guessing that if the battery is at anything less than full charge, I don't have the torque to get the last 10 feet. What is interesting is that acceleration seems fine. I can get to 60 in about 15 sec which isn't neck snapping but not horrible.

So, now it is time for a re-evaluation. My options are:

1. Figure out how to get motors on the front wheels (most desired)

2. Get bigger rear motors and figure out how to install them in the limited space (see photos)

3. Re-gear the drive to a higher ratio (difficult due to available components and loss of top speed)

4. Up the voltage from 72V to 96V or 120V (requiring new motors and controllers)

5. Rip it all out and re-install the transmission for a more standard conversion (least desirable)

Some other issues I still have to address. The chain noise is rather loud, figure out where to put the fourth battery, speed sensor, body work, battery management system, redo front battery mounts, etc..... I knew when I started this that it was a process that probably had no end. There is always something more to be done but that is what I like about it.

Anyway, here are some pictures of installing the rear drive. I also have some video of the first drives but I still need to cut it together into one video.