Carburetors. Vapor lock. Draft tubes. That oily strip up the middle of the roadway.
The ability to order a car with an interior color other than gray, tan or black. You used to be able to order cars with interiors in white, saddle, red, green, light, medium and dark blue as well as black.
You also used to be able to order a cheap stripper car with the biggest engine you could. Now if you want the big engine you have to buy the entire package or trim level.