Thanks for all of the great feedback... It would seem that I can start ordering parts, and that my goals and assumptions seem resonable. I should be close to my weight goal, and within my budget, I will have to see how the acutal performance pans out.. The big variable seems to be the battery and BCM... and it seems that this is the likely the reason you dont see more Electric Karts at the track or Kits for sale...
So I will need to be prepaired to break out the spot welder, soldering iron, and spend some time researching the latest BCM electrical diagrams to get something just right for my purposes...
Is looking like a decent place to start shopping. but I will still need some BCM, they offer a DIY kit, but it seems a little short of my needs and a bit expensive
Also looks like I am going to need a bunch of these cells if I want to get to 72v @500A... The issue I see with these is that most are rated for a 30A draw, and they start to get very expensive when you go up to the 50 or 100A... and even at 50A I am still going to need 200 to build a 74v 500A batt... 6K$ for a 74v 500A 50AH batt @ 50lbs and thats without a BCM... I am guessing unless there is a way to raise the Discharge raiting (eg using ultracapacitors http://www.tecategroup.com/store/ind...roducts_id=126
)... these are not going to be practical for my inital build out.
But even if I could integrate some ultracapacitors, I think I am going to need to go befriend a local Electrical Engineer or two to get some custom BCM technology to keep my kart from catching fire or worse.
I guess one of my goals wich seems out of reach at the moment, was to stick with off the shelf, just a parts list, wiring diagram and a few mounting brackets... this would have allowed me to prototype a system others could go out and buy to race with me... The only real chance I see of this would be to go back to using heavy Optima syle batteries, but these just arent safe in a karting applicaiton, they are way to heavy. I suppose I could go back to the Dwalt packs, and just limit the discharge to something around 20A per pack using the built in BCM, this would just cap me to around 100A draw with my smaller pack size and I would be under powering the motor.