HP gain with multi angle valve/seat

Since the amount of variables are endless....... if you want to think you’re applying some logic to what is a complete guess....... you could:

Decide how much gain in flow(@28” test pressure) the new valve job will provide, in .050” lift increments, up to the lift that the valve will see.

Average those numbers, then take that result and multiply by 2 to come up with a theoretical hp gain for a v8.