That project was based on some very good, but old 24V AGM aircraft batteries that I got a really good deal on. With 196V and 880amps available from the pack and only one small steering wheel the performance of the bike was predictably scary. All the local drag strips prohibited trikes so I was never able to see what I could get on the 1/4 mile. Anyway, this winter the parts from that project were harvested to go into the Miata. I had been scouring CL for cars for many months till I found this one. I was considering my 1969 bug but it is so original and such good shape I couldn't do it. Considered another bug, a fiat spider, and some others but there is an awesome aftermarket for the miata. Throw in disc brakes, great handling, reasonably safe, chasis age and the fact that I could get one in good shape for $1300 and it was the final winner.
The project's goals in no particular order are:
1) A fair weather only car
I will commute in about 2-3 months during the summer. I car pool with my wife and (who is a school teacher) for the other 9-10 months out of the year in our prius. Top down driving means no worrying about heat/AC.
2) Range of 35miles at 75mph down to 80% DOD
I can charge up at work so I am aiming for a minimum range of 35miles at 75mph down to 80% DOD. Realistically I will be averaging 65 on the highway but I want to be conservative. I will have to pay particular attention to motor cooling as 80% of my drive is at 60-80mph. I may have to go to a Warp11 or even dual 9"s but I am really trying to avoid this by minimizing aero drag where ever I can. I need to do more calcs but I'll probably start with my current motor and if I have to upgrade, then so be it.
3) 1000amps for 10 seconds
I want a pack that will make the most of my 9" motor and the Soliton1 controller. I would like to autocross and track it occasionally keeping in mind the impact it will have on my battery life. Aiming for 0-60 in 6 seconds but that will depend on how much weight I strip from the chassis.
4) Simplify and then add lightness
I have seen miata's down to 1600lbs with the stock motor and extreme weight reductions. No top and side windows for sure but I may go so far as no real windshield. It depends on how crazy I decide to get. Look at my last EV and it's pretty clear I don't want to build anything that is "conventional". I want a curb weight of under 2000lbs but I'll have to work for every ounce.
6) Have fun and learn
As a Mechanical Engineer who has spent over a decade in research, design and development "Have Fun" and "Learn" are one in the same.
My plan for the car is two stages:
Stage 1: Get it Running
A pretty straight froward EV conversion using the motor and controller I tested on the Leadwing. I will get it running and registered keeping the rest of the car pretty stock. Many other people have done miata conversions with adapters and mounts being available off the shelf. The big question for me (as is most converters) is the battery pack. Right now I am leaning toward some gray market A123 cells. Specifically the AMP20M1HD-A. I am talking with one guy and have gotten 8 on order for testing.
Stage 2: Get Crazy
The second stage will be stripping the car down to a fair weather only superlight speedster. I will be replacing the front bumper with some custom fiberglass to get rid of the engine cooling scoop but I am toying around with a fiberglass front clip to save more weight. Mazda did a SEMA car that is pretty close to where I want to go:
I will do no real to top, maybe even no windshield depending on how crazy I get. Here is Mazda's superlight concept car that showing where I might end up:
One of my saying is "The cheapest part is the one you don't have to build and install" A variation for this project is "The lightest parts on my car are the ones that doesn't exisit."
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