Hey, I am looking forward to seeing your build! You can check out my thread for lots of ideas of what not to do . It sounds like that forklift motor should probably be fine - I gather that the ratings are very conservative, and people have put some serious power through them without too much trouble. If you have not at least skimmed the thread on forklift motors, I would say its worth a few hours of your time to go through it. You will probably need to advance the brushes to run a higher voltage, which I am sure some of the other members on here will have some info about. As for a 400 amp controller, it might be enough for a little run-about. I seem to recall those curtis controllers were fairly low voltage, and you might not be able to get much of a top speed with them. Hopefully someone else can chime in with some real-world info.