So the heads from MSS were new. They had larger valve seats installed to accomodate oversized valves and had the intake track CNC machined. The exhaust tracks was marked so that a machine shop of my choice, Ridge Reamer, could bore them out and port them.

When I got them back from Ridge Reamer I thought they were done. I started reassembling the heads only to find that the valves were not sitting properly, they extended too far out into the combustion chamber. I called MSS and confirmed that while new seats were installed the valve seats still needed to be cut to angle. This annoyed me because that was supposed to be done by MSS according to their price sheet. Regardless, I didn't want to take these parts back to Ridge Reamer because they would take weeks or months to do this work.

I ended up taking them to Performance Porting in Fort Collins. I met with the owner and explained what I needed. He recommended that in addition to cutting the seats to match the valves, that the intake track be fully ported to finish off the CNC'ed section and fix where the CNC machine had not reached. He also recommended that the combustion chamber be machined out to allow more flow around the valves. It will be machines out to not exceed the cylinder diameter in the head gasket. The valves themselves may be swirl polished.

I am not just waiting on him to finish this work so I can continue reassembling the heads.

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Smll Med Lrg	Smll Med Lrg new oversized valve seats	Smll Med Lrg oversized valves temporarily installed	Smll Med Lrg
Smll Med Lrg turns out I needed the retainer and clips off the old heads	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg
Smll Med Lrg plastic valve umbrella, first time I have seen that design	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg old valves sit recessed. Seats are indeed large enough for oversized valves
Smll Med Lrg new valves sit to far out, seats need to be machined :(