Just curious, those valve have to be quite a bit heavier than like 2.08s, 2.05s.. do they get limited on rpm due to it or just insane spring pressures and beefier valve train?
Years ago ford was always ahead of everyone. Sodium filled valve back before I started racing in the 70’s. Now titanium would be a minimum spec valve with ungodly spring pressure. Remember these engines are torn apart often. Very often