I had thought the 390ci had been dropped by 1969 but not so. In 1970 I spotted a used 69 Boss 429 Mustang on a car lot. The asking price was $2,995.00. It was a bargain but no way could I afford it at the time. The same year I found a 427 Cobra on a Exotic Sports Car lot in Memphis, price $12,500.00. Those were the good old days.
A little known fact was that you could bolt a 390ci into a 1957 or older Ford car. Another bolt-in was the large 430ci Lincoln, Edsel engines into the older Fords. You could run rings around the 283 Chevy guys. Heh!
Another know fact you could drop a 454 big block with closed chamber oval port heads, aluminum intake and 850 Holly double pumper in a 67-73 Camaro, with the stock motor mounts. 400+ HP and the ability to melt your average Kelly raised white letter 70's series tires on the stock rally wheels in 2 weekends. I must have aquired the most traffic points of any 17 year old in 1982 in the State of Florida. Anyone remember "The Kid" from Neba Roast Beef, on Sunrise and Federal Hwy in Fort Lauderdale? Remember seeing my taillights....????