Using a custom-crafted glass head on a three-horsepower flathead Briggs and Stratton engine, YouTuber Matt Mikka shows combustion like never before. Using gasoline and alcohol, he runs the combustion process under varied conditions from a rich state (too much fuel and not enough air) to a lean state (too much air and not enough fuel). See what’s going on under the head in this badass video!
Incredible footage aside, there’s a whole lot of science and mechanics behind the whole combustion deal, as you probably know. But, we’ll leave it to engineering experts to explain the whole process.
Per Popular Mechanics:
There are four visible parts in this engine. On the left is the piston moving up and down. On the right are the intake and exhaust valves (this is a flathead, valve-in-block engine design). Right in between them is the spark plug, which ignites the fuel.
This is a four-stroke engine, which means the full cycle has four steps. Step one is the intake valve opening and letting air and fuel into the chamber while the piston moves down. On step two, the piston moves up, compressing the fuel. On step three, the fuel is ignited, and the force of that ignition pushes the piston down again. And finally, step four sees the piston move upward again, forcing the exhaust out of the newly opened exhaust valve.
Pretty sweet, right?
This post was originally published on January 17, 2017.