Id think that youd need to use a pressure gauge to see the difference -gain - at normal speed.

I did that in the army on my chevy 4 banger and got a gain at 60 but it was made up out of coke cans sectioned and taped together with scotch tape to form the tubing/ piping.

I was very poor and had time on my hands so coke can tubing on a one barrel carb was my way of experimenting. could cut the can with scissors and tape was available and it was sorta cold ( can ) air inlet with a scoop to catch air. YOUTH!!!!