"When the first
cobra came out in 1963 it featured a 289 cid V8 small block engine. This
car was said to be a hit but, Carroll Shelby had bigger plans for his
car. Then in 1964 Carroll was able to build his Shelby powered with a
427 Big Block V8 engine. This was Carroll Shelby's dream that he could
design and build a car that would be able to compete with the “Heavy
Weights” of the times. This first 427 Big Block version of the Shelby
was strictly for racing, But in 1965 the first commercial version of the
Cobra hit the streets with a bang. Th 1965 Shelby Cobra featured a top
speed of 165 MPH and had a tube frame with a redesigned coil spring
chassis."
Credit: Car Junky