Since the largest part of the replacement cost is in the labour involved in changing a timing belt, it makes sense to replace all the associated components at the same time. Remember that the cost will always be considerably less than the cost of buying a new or rebuilt engine if you choose to leave the belt beyond the recommended replacement time. Also on most engines the cam drives the distributor (or on engines with distributorless ignition systems the cam position sensor) incorrect phasing of the camshaft affects ignition and fuel delivery on engines with sequential fuel injection.
Pro-Torque Automotive Products can supply all components necessary to complete a timing overhaul on a wide range of European, Japanese, Korean and Australian vehicles. With over 400 part numbers in the range complete with Installation instructions where necessary and a mileage sticker to record change details.