magnetic levitation is tricky business, to get the speed that you want you need to have a perfect alteration of poles to propel your train. you also need to calculate the correct strength so that it actually moves when it's told. i tried this once before using a 4017 for my own amusement, it was just supposed to move a bar magnet across a desk, the problem was that it kept veering off course. i have to ask, are you prepared to calculate all of these variables that are inevitable going to encounter? today's Mag-Lev trains are controlled by sophisticated computers ouboard the train that can keep a constant state of propulsion.