An invert is a rule that reverses the front of a starting lineup by a set number, so the fastest qualifiers start behind slower ones and have to pass their way forward.
An invert can hit the heats, the feature, or both, and the size is usually written into the rulebook — though not always. IMCA scales its feature invert to the number of heats: top five with one heat, top 10 with two or five heats, top 12 with three, four or six — all ordered by a driver’s three-event point average. IMCA also inverts the heat lineups themselves on points nights, running the lowest point average to the front and the highest to the rear. Tracks set their own and some leave part of it to chance — Slinger Super Speedway sets its feature invert from “a spin on the invert wheel” plus a set number based on entries — so read your rulebook rather than assuming last week’s invert carries over.
An invert changes what a good qualifying run is worth — sometimes being fastest hands you the worst spot in the field — so know the number before you decide how hard to run your heat.