The ASP 178 crank pulley comes in a kit that includes new belt, water pump and idler pulleys to slow them down. The only accessory that suffers is the alternator IF you spend lots of time at redline…. like me. The supercharger pulley is cheaper and easier for sure. The instal for the crank pulley isn't for the faint of heart. Watch out for cheap S/C pulleys. My first pulley was a 65mm aluminum Code3. It didn't last a year. My advice would be to avoid the aluminum ones.

Les