Why are the 348 and 409s called “W” motors?
When the 265 came out in 1955, it’s larger size was greatly accepted by the public and Chevrolet realized that this trend would continue far into the future with bigger and bigger engines. The problem is the 265 could only grow so big (to 327 cu. inches). Another problem was the small block had torque limitations in a low rpm range that made it less than desirable for heavier models w/automatic transmissions and unsuitable as a truck engine. Chevrolet came out with 3 test engines to meet this problem labeled, “W”, “X”, and “Y”. The “X” and “Y” were bored out versions of the 265 displacing 300 cubes. The “X” model kept the 3″ stroke while increasing the bore to 4 inches. The “Y” engine had an increased stroke (3.3 inches) and a bore of 3 13/16 inches. Neither were what they were looking for but these engines did lead up to the 283. Last was the “W” engine. What was needed was an engine with not only another 50 cubes but one that had room to expand 60 inches beyond that. It also had to b
