first off, a pulley doesn not change displacment, the arrgument ppl bring forward is, say a cobra, has a 4.6, and the s/c is a 2.2 soo that then makes a 6.8 motor, but i dont really belive that theory tho. no body ever said changin a pulley will add displacemnt, mr. know it all u should konw that a pulley change will just spin the screws faster thats all. i never knew a change of pulley would add more cubes to a blower. Soo wait if u say that, then me puttin a smaller pulley on my cranks should increase my motors cubes?!?!? awesome :hsugh: