If you use @Inwo 8kw motor, a sevcon controller, lithium batteries and a 8.9/1 gear box top speed is 71mph. I have not hit 71 but @MikeKC and I got it to 68mph via gps. I do not recommend trying those speeds, it starts floating and getting sketchy around 60mph. On regular flat roads a steady 50-55 is no problem with more mph to spare. This setup can run 50 mph uphill with 4 people in the car all day long and not get hot. You will be real happy. A word of advice that will save you alot of money and many frustrations. On your project do not try to reinvent the wheel and go with a proven setup.
With alot of input and guidance from @MikeKC I was able to go my own way with my lithium setup but it was not to far of a deviation from what has been proven to work. The package looks different, it took a lot more cabling, fabrication and the end result was a 128amp hr pack that gets 32-35 miles per charge (pedal held at 75-90% entire time).
@Jatgm1@JarJarJava here is a pretty accurate cost amount for your question give or take a few hundred dollars.
$1,800 lithium
$350 new charger
$1,500 ac motor and controller
$200 2/0 tinned battery cables & glue lined shrink
$40 tin plated battery cable connectors
$900 complete front end suspension from a 2014
$200 misc parts & supplies
35-40 hours of labor (No cost, I did myself)
Grand total $4,990
I have not yet installed one. I made this 23cells and charge to 93.38v. This way it is conservative with the charge (charges to 4.06 per cell, max is 4.2v) and when they are discharged to 3v you are at 70v which is what the delta charger needs to see to kick on and charge. If one cell starts to run away when charging at a charge of 4.06 chances are the pack will reach 93.38 and cut off before something goes really bad. I know that I need to and plan to get one installed. I also do check the individual cell voltages with a meter often.
I have a set of fiat cells sitting in my garage. I’ve been trying to decide what I’m going to do with them. Was more curious to see if you figured out an easy way to plug into the OEM harness. Wiring seems trivial and looks like you can pop off orange cap to chase down the wires. Haven’t spent much time with it. If I do end up messing with them and figure it out, I’ll let you know.
Thanks for posting. Cool setup. 60+ in a GEM sounds terrifying but the fact you designed and built it to go that fast is fascinating to me!!!
@Erniea15 the orange covers come right off and snap back on with no problems. I did see a set of the end connectors on ebay once specifically for these cells. I ended up cutting off the oem plug and using Wago electrical connectors. Super easy. Their spring loaded to hold wires in place and male/female ends snap together easily. Well, I have to admit my dad’s buddy who’s shop I build it in was an airplane mechanic & engineer. He also built midget race cars from scratch for many years. He gave me some help, many suggestions and went over it with a fine-tooth comb looking for items that may fail, needed beefed up or replaced since it was going to be going 45 mph faster than it was designed to do. It ended up being wheels, tires, bushings, front/rear suspension, a few welds and brakes. The rest of the car is pretty bomb proof.
