Bought a new vortech tuner kit. No Fuel pump/injectors/Maf
Will I need to buy any of these to put it on a stock 2002 mustang GT? Running the stock pully!

 

You will need to by a high volume fuel pump (Vortec uses the Ford Focus SVT pump, if its not aftercooled, you will need to at least step up to 30lb injectors. Your MAS will work. You will also need to have the ECM recalibrated by either Vortec or your tuner BEFORE YOU START THE CAR. You will probably end up buying a lot of stuff if your just got the tuner. Hey good luck!!!!!