Geez, we could probably start a whole thread on engine explosion stories LOL! Here's a related one, that my Dad told me 40 years ago. Apparently a bunch of his friends had an old 40 Ford convertible that they liked to run in parades in the mid 1950s, in Youngstown Ohio. They had rigged it up with a second coil, connected via a long wire to a spark plug in the tail pipe. They had also put a wooden box under the hood, and a big steel plate. The box contained a hammer. The car had rust holes in the floor. For the parade they would all get into the car carrying old pistons and connecting rods. Anybody see where this is going?

As they idled past the judging stand they would pull the choke to make the engine really rich. It would backfire a bunch of times, and the spark plug would ignite excess fuel in the tailpipe, shooting flame out the back. As soon as this was happening, they would start dropping the pistons and rods through the holes in the floor, so that as the car continued to move forward it looked like it was dropping parts on the ground. Finally after about 30 feet of this they would stop the car, all four would jump out, grab the pistons and rods, and run to the front of the car. Open the hood, put all the parts in the box, grab the hammer and pound the steel plate to make a bunch of noise. Close the hood, get back in the car, and drive away. Apparently, they were one of the more popular parade attractions LOL!