How about some trade names from the old days? To name a few: High-Test No-Nox Ethyl Hi-Octane Anti-Knock Supreme Super Hi-Test Benzol (Ford brandname) Pure-Pep Texalene
I've got "Fuelish Pleasure" on my tank in gold leaf, that's the name of the car. The cap says "g*** hole"(not a typo) but could have gone with "GA$ HOLE"
I always tell my wfe I am going to the fosil fuel liquidation when I am getting gas in the old truck to do some crusing.