An object lesson in why a larger bore is better....
Think about it. You've got a 4" bore, looks like. Those valves are 2.02" and 1.6", or larger, for a total of 3.62" or more, and they're off to one side of the cyl besides, where there's not the full 4.0x" available for them to be in. How could they fail to be close to the cyl wall?
It has nothing to do with what kind of heads they are, as such. Wouldn't make the least bit of difference what brand of heads; if the valves are that big, and the bore that small, then they're going to be that close.
This is one of the reasons why putting larger valves in a set of heads can actually HURT performance, by actually REDUCING flow. Doesn't hardly matter how big the valve is, if all the material coming through it has to squeeze through that little crack around the edge, to get into or out of the cyl. Why, for example, it's not good to run 2.02" intakes in a 305, even if they don't outright hit the deck.