Ford Small Block 3 Groove Black Crankshaft Pulley 6.75 Diameter. Need some good-looking pulleys for your street ride? You can’t go wrong with these chrome crankshaft pulleys will help you maintain water pump efficiency with quality and style. Water pump shims may be required for proper belt alignment! Due to our multiple sales channels, suppliers and manufacturers, the inventory we have in stock is can be wrong from time to time. In the event that there is any problem whatsoever, we will contact you as soon as possible to inform you. We want to make sure that you are very pleased doing business with. Sparky’s Parts Hub.