I have a crank pully on my h22a. I have noticed very little by installing it. But i didnt have p/s or ac either. I do know if your harmonic balancer has a big ass chunk missing out of it the engine vibrates really bad. (i know because mine had a chunk out of it what i dont know is how it got like that. Thats y i changed to the small crank pully.) It actually works as a harmonic balancer because once installed my engine quit vibarating. Its actually VERY EASY to change. All you need is a prybar, 1/2 drive ratchet, a 19mm socket, a small 1/2 extention, and a foot long pipe that can just barely fit on the end of the ratchet. Take all your belts off and then stick the prybar into the opening of the transmission(where you would check the timing) and brace it into the teeth of the flywheel. Take your 1/2 ratchet with the pipe for added leverage put your 19mm with the extention on the crank bolt and start pullinor pushing it will take a little bit of effort but once you break it loose its smooth sailing from there. Intallation is reverse of removal. Just MAKE SURE the little pin hole in the center of the pully is lined up or you will put it on crooked and you will fu*k some sh*t up.