Like roller cam or solid flat tappet or what? I guess what I would consider is the lighter the valve train is, can I get away with less valve spring pressure. How much I could gain in power (lower et) and greater engine longevity (more runs per valve job).
Somebody would have to explain to me how valve weight affects spring pressure. It's the lobe lift that dictates spring pressure. At least that's how I see it......maybe I'm misunderstooken.