An assembled A57 Multibank engine
In World War II aircraft and tank engines were in short supply. Manufacturers were hard pressed to keep up with the demand. For the early variants of the M4 Sherman tank, Chrysler developed a unique engine comprised of five 6 cylinder engines in a single assembly which created a powerful 30 cylinder tank engine called the A57 Multibank engine. This Dodge 6 cylinder engine was used in the Dodge Windsor automobile before the war and was adapted for this purpose. Tooling already existed to produce the Windsor engine in large quantity.
Tanks with these unusual engines were supplied to our Allies, most notably the British. The engine produced 450 horse power and was very effective. It was reportedly very smooth and reliable and could absorb a lot of punishment. Does it have anything to do with classic guns? No but its very cool.
Beautifully restored M4 Sherman with a Multibank engine.