This OEM cylinder head is designed to use the stock camshaft grind. Most higher lift aftermarket camshafts will not work due to the springs going into coil bind. LC Engineering recommends only using a stock grind camshaft. If you do use an aftermarket camshaft you will need to verify that the valve springs do not collapse together and create a binding issue. When the cam is at max lift you should have a minimum of .050" between coils.