Sunbeam Tiger
In 1959, Sunbeam presented the Alpine, a nice-looking roadster with reliable mechanis and small 1.5 or 1.7-liter four cylinders. But the company soon realized that it needed much more than four cylinders to be competitive in the sports car market. So they called the legendary Carroll Shelby and asked him to turn the docile Alpine into a performance car (via Hagerty).
Shelby designed the Sunbeam Tiger as a muscle car version of the Alpine by installing a Ford 260 and later 289 V8 engine, redesigning the suspension and steering. It was the first British roadster with a proper V8 rumble and performance. Finally, Sunbeam had a sports car, and Tiger was fast and powerful for the standards of the day. Most of the cars produced went to US buyers and when production ended in 1968, Sunbeam had built around 7,000 examples of the Tiger.