Challenger SRT Hellcat

Make
Dodge
Segment
Coupe

The days of the internal combustion engine are numbered - numerous states have been passing laws banning the technology in the near future, and while some manufacturers still believe in the technology, others are throwing in the towel completely. The internal combustion engine has been around for the better part of a century, and in that time has seen immense improvements, but to many, the way it works is still a mystery. Now, thanks to an incredible video by TRO Designs, we can see exactly what happens inside the combustion chamber thanks to a transparent cylinder and glorious 4K slow motion. The results are as mesmerizing as they are educational.

Unfortunately, we don't get to see the wonders of internal combustion taking place on something cool like a Dodge Challenger SRT Hellcat or a McLaren Senna, but instead, we get to view this miracle of man on a more humbling scale. The engine used in the video is a bare-bones 1977 four-stroke Honda XR75 engine with a deburred and hand-polished piston, a lengthened acrylic cylinder that brings the compression ratio down to 8.7:1, and finally, a set of Teflon cylinder rings. The rig is built on an aluminum frame. The video shows extensive footage of how the piston rings are made, the engine assembly, the installation of the cylinder, and even a compression test. According to the video description, the builder uses Motul 300V 15W-50 engine oil to lube everything up.

At 12:13 the engine finally starts running, and we're impressed by how healthy it sounds. At 12:49 we finally get to see some slow-motion footage that clearly shows off the combustion process, and at 14:47 the engine is run at full throttle. We even get a sneak peak at the timing chain in slow motion. Possibly the most fascinating part of the entire video is seeing how efficiently the exhaust valves extract fumes from the cylinder chamber before new fuel is introduced. We can't imagine that this little engine could run a decent amount of time on an acrylic cylinder housing, but the slow motion footage makes all the effort totally worth it.