stock i dont think you'd beat any of those cars, if the driver's were equal.
with bolt on's ONLY (no nitrous), you may stand a chance against the Si and the base RSX, but i doubt it. I drive a stock Si and raced an EX with bolt on's and won by at least 3 car lengths. i dont know if the Dx has more power stock than the Ex, but i dont think so.
but no, you will not touch the typeS without the nitrous. but nitrous IS cheating, unless your running that 75 shot all day everyday, it is not part of your motor, which makes it cheating in my book.