Well, I put the smaller 2.80 pulley on the car and also replaced my ignition lock cylinder. I do not have the anti theft chip that some stangs have, but when I start the car, it runs for about 5 seconds, then shuts itself off. So, now I have to tow the car to the dealer to update the PATS system in my computer. Can't wait to see how much they charge! Now I am scared to death that the mechanics are gonna "test" drive it after it's fixed. I hate giving my car to people I don't know.