Is there any way to figure out or calculate fuel consumption of piston engines for aircraft? I'm looking at different engines in a book, and while jet engines have useful values like thrust, bypass and pressure ratio, piston engines only have power output and weight.
Propeller efficiency plays a role here, I guess, but it's not at hand so I assume all engines use the same propeller in this case.
Would the easiest way to calculate such a number be to find the maximum fuel capacity and range and from there find out how much fuel each engine uses per hour?
I've asked a similar question before about turbojets and turbofans and received good answers - sadly, piston engines are completely different...
EDIT: To clarify, I am looking at airliners powered by piston engines and wish to compare them.