I think the OP is talking about a gizmo that goes in the inlet manifold and is claimed to boost power. A claim I consider dubious. Check it out for yourself. https://www.mikes-afordable.com/product/A9425H.html
In the 60's companies like JC Whitney, Warshawsky and Rick 's (Rick Packs) sold similar devices that claimed 15 to 25% more power, more gasoline mileage and etc.
Sears, Wards, and Western Auto also sold them.
The standard local joke was that if you used all ALL OF THE DEVICES that your gasoline tank would always be full and you could sometimes sell the extra gasoline!
It is well recognised that a car runs better on a foggy night. Cool air and a bit of moisture help the engine. I imagine these devises imitate those conditions.