SM Head Modifications on a budget

I'm fabricating a 5" long 2% tapered intake entry plate that will act like a perfectly straight intake manifold runner. I want to test the pushrod pinch changes with a different entry plate. I hate the phrase but I'll use it here. What if the flow bench is lying to us? With a short entry plate we basically have a venturi right at the port entry. That could do weird things and certainly different things than in a running engine.

Can you show us what entry plate you are using.