"The Bizarre Engineering Marvel: Unveiling the Commer Knocker Engine"

The Commer Knocker, also known as the TS3, was a unique engine used by British commercial truck manufacturer Commer in the 1950s and '60s. It featured an opposed-piston design with two pistons in each cylinder, and one crankshaft instead of two. The TS3 had a distinctive idle sound and was remarkably powerful for its size, producing up to 117 horsepower and 310 lb-ft of torque. However, production ceased in 1972 when the four-cylinder TS4 replaced it.