Carburetor scoops do they make a difference?

It's hard to accurately measure how much of a difference it actually makes since trying to test the performance on a dyno with a scoop is difficult to impossible. You can use a blower fan, but getting an exact measurement is tough because reproducing the wind and air flow outside of using a wind tunnel is nearly impossible.

I'd say the additional performance is marginal at best and using a scoop or carb scoop is more for looks.