Thinking outside the box
This is a subject that can be bantered backwards and forward for years.
First thought is that there is little to compare. The modern technology of heads has outpaced most of the common mechanic's limited skills. We have seen MANY types of heads over the years and we still have to deal with reality. The corvette even had two ports per cyc. a few years back ( not sure what they have now ). What I'm pointing to is that now we have computers to make-up for shortcomings of head designs while allowing the heads to flow big numbers and big hp ratings. Most of us are still in the middle ages and use carb's that are far less forgiving. I give you that we can put the big numbers up with our engines but how many engines that we have are TOTALLY COMFORTABLE in a traffic jam going to work?
The modern cars have a HUGE advantage and makes the average rodder look sick in some areas.
I think someone will soon come up with a computer upgrade for the older cars to do much better in daily manners.
But I still would like to have a set of the W-2 heads and valve train. The W-2's have been around since the 70's but still serve as a benchmark. Wonder what they would have been like if they had been designed with swirl technologies built in? W-2s were made because there was a demand for a better head for the round track boys that demanded an iron head for class requirements and for the drag boys that just wanted more, like the Pro-Stock boys. If I remember right it is the head Bob Glidden used on his 340.
Sorry, just think out loud.