Mercury, Edsel and Lincoln. This showed up on the '58 models and continued on beyond service as options in Edsels, Mercurys and even in Thunderbirds (Theoretically, the should have acronymt it the M.E.L.T.. But I suppose, doing so would confuse pundits into thinking that this engine had a reputation for overheating?) up until 1960 and then continued service in the Lincolns until Ford's 460 replaced it in 1968. Marine applications also employed it. It was a massively cast wedge-blocked engine, similar to the Chevrolet 348-409s, except that Ford's version unfortunately didn't have canted valves. It was modelled after a larger Ford truck engine. It had early successes in drag racing and reached its peak, as a 400 horsepower option in the '58 Lincolns with 3 2-barrel carburetors and high compression. Because of differing fuel qualities, nation wide, compression was dropped, beginning with the following year: https://www.curbsideclassic.com/blo...carb-mel-430-engine-taming-the-thirsty-beast/