I had a 1966 El Camino with a built up 400 small block that was a 1972 block. Everything passed smog except the visual and I was refused to pass. After about 6 visits to smog stations I finally found one that would pass it. The whole smog thing is bogus anyway, some models of cars in the late 70's or early 80's actually put out more polutants when calibrated as they require when less can be released when properly tuned. Some lobbyist for a smog pump manufacturer is responsible for getting the legislature to pass these laws, at least in California.
