Mr. Shelby put Ford V-8 engines in at least two English sports cars. I believe that the Sunbeam Alpine became the Sunbeam Tiger when equipped with the Ford 260 inch motor. While this was happening, Shelby hatched a deal with AC cars which resulted in the AC Ace becoming the AC Corbra.
Trouble was, Sunbeam was manufactured by Rootes of England, which had a Chrysler connection at the time. Ford motor encouraged Shelby to settle on AC and that ended the Tiger production.
Someone more knowledgeable on the era can correct me if there are errors in the above...