Horsepower Per Cubic Inch Is A LIE — And The Math Proves It

Everyone in motorsport uses horsepower per cubic inch to judge an engine. Magazines use it. YouTube uses it. The industry treats it like gospel. It's a lie. In this video I'm going to prove it with four engines: an RC Nitro, a MotoGP bike, an F1 Cosworth V8, and a NASCAR Cup V8. Horsepower per cubic inch measures one thing and one thing only, how fast an engine can rev. It tells you nothing about combustion quality, engineering excellence, or actual efficiency. The metric that does? BMEP. Brake Mean Effective Pressure. And when you run the numbers across all four engines, the result will change the way you read an engine spec sheet forever. Jake Bain, fourth generation motorsport, cylinder head porting, intake manifold design, founder of Einstein Motors.