So about 40 years ago, working at a service station as a front end mechanic, I had a customer with a early K5, 454, twin ram air cleaner.
I encouraged him to do what AIS does, he did, said that it was really effective, above 45 mph, no one could touch him when he punched it.
Having said that, going to their site and their gallery, some variant models look totally ineffective, like the '57 Chevy PU.
Others like the sedans with the flat ram inlets flanking the radiator-under the hood? Where is the forced air coming from? The gap between the hood and front end?
More like reverse effect as the air blows past the gap creating vacuum...