Welcome to Sunday Matinee, where we highlight classic car reviews or other longer videos I find on YouTube. Kick back and enjoy this blast from the past.

Formula One. Formula Two. Formula Three. Formula 3000. Formula Ford. Formula BMW. Formula Renault. There sure are a lot of varying racing series out there with the word "formula" in the name. Surely you'd like to know what they'd all mean.

Well why don't we start on one of the most 1970s-iest ones of all, Formula 5000? It officially ran from 1968 to 1982, and was supposed to be a low-cost open-wheel series meant as an SCCA-backed alternative to the top tier of motorsport, Formula One. There weren't very many restrictions, besides the fact that engine capacity was capped at 5000 cubic centimeters of displacement (hence, "Formula 5000").

At first, most people used stock-block Chevy V8s, but as the rules allowed F1 cars to participate, those started showing up on the grid in due time as well. The vehicles were pretty damn powerful for the day, with around 500 horses to start. Costs spiraled out of control, though, as they are wont to do, and manufacturers soon dropped out for the more glamorous Can-Am.

Still, it's a fascinating footnote in racing history.

H/t to Henry Hope-Frost!