"California and Denver" jetting.
Back in the '70s, I worked at a parts store for awhile. We sold "replacement" carburetors. No matter who walked through the door, a replacement Q-Jet was the same, 250 to 455 Cu In Pontiac, whatever. Same deal for Motorcraft and Holley. I bought one of those Q-Jets to put on my 327, but it needed work to make it right.