Well I just bought a 1994 Mazda Miata for my next EV project. I am reusing parts from my last EV project, the Leadwing.
For those not familiar with the project it was a 1987 Honda Goldwing trike that I converted to electric mearly to learn and act as a stepping stone for this project. 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 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 as 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 Reduction
s. 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 a ton but I'll have to work for every ounce.
5) $10000 Budget
The $8000 is for the batteries, BMS, instrumentation, and adapter, cabling, materials, etc. Given my other goals mean I have to go Lithium and a budget to match. Another 2k for a charger.
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 going to order a few for testing.
Stage 2: Get Crazy
The second stage will be stripping the car down to a fair weather only superlight speedster. No top, maybe even no windshield depending on how crazy I get. 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. I will fab a real roll hoop/cage for protection. Without the constraints for a top I can make a cage that will provide real head protection. I used to run SCCA time trials and it would be fun to do so again.
First step now is getting the title transferred. I always do this FIRST when starting a project. I don't want to strip it down and then tell me I have to drive it down for a VIN inspection.