Valve Issue

[halg]

I am rebuilding the engine in my Fiat Dino Spider. I have found an issue that could happen in the 124 TC engine(since they both use the same tappets and shims). Has anyone ever seen a reference dimension for the minimum length the end of the valve should be above the upper spring seat? What I have found is the end of the valves were ground short enough for the tappets to rest on the spring seat instead of the end of the valve. During valve actuation the tappet was pushing the valve open using the spring which caused the valve keeper to wear the groove and created a burr that kept the valve from being able to be removed(larger than the valve guide) It also kept the tappet from being able to rotate.(cuused undue wear on the shim) In this engine it was caused by fitting the wrong valves(different years used different valves)
In the Fiat repair manual there is a reference to tool A96218, which is used to measure from the head surface(where the cam box mounts)to the end of the valve stem. Does anyone know what that dimension is? One of GC's head prep shows him setting the dimension to 41.45mm. He states the std is 40.5mm. Usually you buy valves and expect them to be correct, has anyone ever seen a drawing with dimensions of the groove location in relation to something? It is perfectly accectable to grind the end of the valve stem to obtain the proper dimension. No problem unless the groove is in the wrong location. I realize this is pretty technical and most won't be doing this work, but an issue just the same.
Hal

[So Cal Mark]

have you looked in the factory manual for that spec? I'll check mine on Monday and see if it's in there