Development potential of piston engines

[fliger747]

A litle explanation about BMEP, it is not directly a measure of an engines power as volume is taken out of the equation, sort of a power per volume figure. On an engine it is measured by a "brake" torque meter. The range of BMEP values for piston engines is known, and in initial design a target BMEP can be used to calculate the desired displacement for the engine HP goal.

 

[Shortround6]

I would also note that for a given type of fuel (87 octane or 100 octane or 100/130) the upper limit of BMEP was pretty well known. ( it did vary a bit depending in cylinder size and cooling)