1973 was 20 years before that. Catalytic converters were introduced then.
Actually, the 1975 models were the 1st to use cats in the US, although unleaded gas was introduced a few years before that. I remember that Shell called their low octane unleaded, "Shell of the Future", and sold (not much of it) along side of leaded regular and premium in the early 70's. Some vehicles (lean burn Chrysler engines, Honda CVCC's, light duty truck and SUV engines and maybe a few others) went several years past 1975 without cats.
The reason for stopping lead back in the 1970s in the USA was to avoid poisoning the catalytic converters.
That's true. Cat poisoning, not children's brains, was the reason that unleaded gas was introduced. Up until around 1980, there was no computer monitoring of car engines, so some people yanked the cats off their exhaust systems and replaced them with "test tubes" to free up back pressure and enhance performance. Early pellet type cats would sometimes clog up and choke an engine. "Gutting the cat" was also used to free an engine while fooling visual smog inspections..
Those days are long gone, now, and any attempt to defeat modern vehicle emission systems will hurt, rather than enhance, performance.. |
