The gasoline engine has taken so many different shapes and forms over history, from familiar inline-fours and V8s to beautiful radials. But someone has to maintain these things, and more elaborate engines may be equipped with dozens of spark plugs. Chrysler once made a tank engine that had 60 of them! The Bishop wrote about the glorious Ford GAA, but he really only scratched the surface of tank engines. Hoser68: This wasn’t even the weird engine for the Sherman.