Ron,,thanks for the help, but i believe that the alpha 400 would be very similar to the mystery 4200kv at 28 mm in diameter, which is to wide to fit up into the exi450 LE frame. (the width of the LE frame is 22mm and the motor dia of 28 mm is 6mm to wideo) do you have the LE (limited edition)or one of the other models?