Curious about AAR/TA Heads

You'd have to install pretty large valves and open up the bowls a lot before the pinch of the pushrod becomes the limiting factor.

I'm guessing the T/A rules didn't allow moving pushrods so they had to cast them in.

Bob Mullen would move ports higher and wider by adding metal and moving pushrods to 340 heads for Pro stock and other high end racing which lead to the development of the W2.