Comparing engines is a little difficult once you get past peak horsepower and torque numbers, since there is a multitude of factors to consider. If only there were a tidy way to compare the efficiency and power potential of different engines. Well, Engineering Explained posted a video explaining precisely that formula.
Let’s get one thing out of the way right away: Nothing in this video is simple or easy. Schools have retreated to remote learning right now and this 16-minute video is the equivalent of an entire semester of high school math. Hang in there, though, because the calculations Jason works up reveal some worthwhile points on how you can compare engines of all layouts.
The bulk of the math involves calculating the average force pushing the piston down during the combustion stroke. While Fenske incorrectly defines that force as an explosion—the fuel and air mixture is burning, not exploding—he does have some solid reasoning for using this statistic to compare a Ford V-8 against a Ferrari V-12 with data rather than unsubstantiated opinion.
Whether or not you’re sold on Fenske’s formula, it adds up to an interesting thought experiment. What do you think? Is it really worth comparing powerplants in this way? Let us know whether this video simply caters to math nerds or whether it offers a helpful platform for comparing vastly dissimilar engines. Don’t worry, we won’t make you show your work.