Ok, Again I am not a head builder. But I discussed your comments with my builder and didn't leave until I thought I understood him.
First my damage: I have bent and cupped valves. They are not tulipped nor have any of mine ever been tulipped. The bending is being caused by piston interference which is absolutely happening from an over rev, The over revs have never exceeded 8K though. All damage has been on the exhaust side and primarily on #2-4 cylinders.
Per head guy, tulipped valves are not caused by them impacting the seat. That is indeed the force that creates the tulip, but is is excessive heating of the valves that conditions the valve metal to be tuiliped when it impacts the seat at normal impact force. He agrees with Jim that it is likely the metal has been changed if this is a recent problem. That said, he states that the valve bouncing on the seat is causing excessive heat. When the valve seats and stays seated by correct seat pressure, then the valve cools. That said, if we increase the seat pressure, do we then exacerbate a tulip issue?
The bending of my valves is happening in the over rev and banging into the valve relief of the piston. Yes it is an over rev, but not a high over rev. If it is floating at 8K rpm enough to interfere with the piston, then the valve is still floating over the nose of the cam at 6.5 to 7K as well. Just not enough to interfere. So the question becomes how much spring pressure and rate do you need to control the valve at our RPMS? He states that 35 seat and 75 over the nose is not enough and that we could add 20 to 30 lbs without having to worry about parasitic power loss. Besides shimming he stated we could lighten the retainers and get a little improvement with our current springs. Probably not enough to keep from bouncing and floating though. The cupping I am seeing is also caused by too low of seat pressure. So in his opinion, every failure type I have seen plus the tulip you guys have seen would be improved if we had heavy springs.
Maybe the answer is to just not over rev the engine. But that only solves the valves being bent. It does not fix the cupping and potentially the tulip. If what he is saying about heat is true, then over rev or not, our engines are running hotter than need be and we can get more life and reliability out of the motors by allowing us to shim or to run different springs.
IMO, taking a run at the other spec body will not work unless SMAC approves for SCCA. The reason, and I would agree with the reason, is that it is one thing to ask competitors to run 2 different sets of tires, it is something else to ask them to have two different head configs. Two different head configs would be cheaper for me to deal with if I ran both orgs than having to deal with two different tires. But for the average guy, this would be more expensive than two different tires.
So in spirit of spec class racing we do not want to create additional costs for competitors. But I think we can all agree that you are not competing if you don't have a built head. So if you are building a head, what is the additional cost of allowing us to run shims? $10 maybe? What does a new valve cost? What does it cost to have a valve job done for cupped valves? What does it cost for unnecessary over rev damage?
Anyway, I have met my obligation to my head guy to pose the issue to you guys to consider.