The actual valve lift depends on a variety of factors. Valve sring coild bind, Clearance between oil seal and retainer are the most improtant. Ie, if you instal a cam with .560" lift and there is only .500" lift of clearance bewteen the oil guide's oil seal and the retainer then the retainer squishes the oil seal and takes the tops off of the camshaft. These engine being hydraulic roller lifters the pushrods would probably be damaged after the oil seals instead of the cam lobes. Maybe the rockers would break of the studs bend?
The porting shop may have included the valve lift clearance if you asked for different springs, retainers or changed the valves. The way you check the valve lift clearance is by using the retainers and oil seals with no springs and measuring the actual clearance by manually moving the valve up and down while measuring the actual movement of the retainer/valve with a vernier or dial indicator. If your cam is too large, or you use racing springs the way to get increased clearance is to cut the spring seats, use different thickness shims or change the retainers. Then purchase the correct springs and the specs will include at what compression coil bind occurs. That's why cams are usually bought as a complete kit.
Because it's so complicated not many people do it themselves, they use a shop.
Ted
The porting shop may have included the valve lift clearance if you asked for different springs, retainers or changed the valves. The way you check the valve lift clearance is by using the retainers and oil seals with no springs and measuring the actual clearance by manually moving the valve up and down while measuring the actual movement of the retainer/valve with a vernier or dial indicator. If your cam is too large, or you use racing springs the way to get increased clearance is to cut the spring seats, use different thickness shims or change the retainers. Then purchase the correct springs and the specs will include at what compression coil bind occurs. That's why cams are usually bought as a complete kit.
Because it's so complicated not many people do it themselves, they use a shop.
Ted