That's a question I had re fuel system compatibility... Is engine displacement the comparable number? Or is engine output a more accurate measure of what is needed?
IE is a system for a 120hp engine going to be a closer match to a basic Stovebolt than one from a 235(ish)ci engine that puts out 225hp? I would think that putting in the fuel needed for the output hp would be more accurate, but I've been (very) wrong before.

Current fleet (subject to change w/o notice)
\'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run.
My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787.

Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.