Ken makes a great point I had never considered before: we all know more rpm = more hp but its his comments on CID that was news to me. Point is, he's stating that a 300 CID engine, as rpms go up, becomes essentially a 600 CID engine. Food for thought!
RPM IS THE KEY TO POWER
The one question Kenny Duttweiler has always been fond of is, “How do you determine how big an engine is? What is the guideline for the displacement of a 300ci V8?”
He acknowledges that by convention we say a 300ci engine theoretically displaces 300 ci of air every 720 degrees of crankshaft revolution, but Kenny went on to say, “Then we have to [think about] what the swept volume is at all these various rpm the engine will run at. Like at 5,000 rpm, is this the point where the engine is 300 ci? But then if it’s efficient at 10,000 rpm, then is it 600 ci? That’s really what it is because if you pick the point at which it is 300 ci, every time it goes around [at a higher speed] it’s adding cubic inches. If the 300ci engine at 10,000 rpm has the same volumetric efficiency as a 600ci engine at 5,000 rpm, they should essentially make the same horsepower. That’s why a Formula 1 engine at 18,000 rpm makes so much horsepower. They’re 140 ci at some point. But the rpm makes them appear bigger. But you can’t force an engine to rpm unless it can breathe.”