Indicated Mean Effective Pressure Calculator

Calculate IMEP to understand the pressure developed inside the cylinder during combustion, before mechanical losses.

Power from combustion (before friction)

IMEP Results

IMEP (PSI)

33.3

IMEP (Bar)

2.29

IMEP (kPa)

229

Est. Peak Cylinder Pressure

100 - 133 psi

Work Per Cycle (Total)

338.46 ft-lb

Cylinder Displacement

500 cc each

Power Per Cylinder

100.0 HP

Combustion Efficiency

Below Average - Room for improvement

Friction Loss Estimates (88% Mechanical Efficiency)

Estimated BMEP

29.3 psi

FMEP (Friction)

4.0 psi

Friction Power Loss

48 HP

IMEP vs BMEP

IMEP represents the work done by gas pressure on the pistons (indicated work), while BMEP represents the useful work available at the crankshaft (brake work). The difference (FMEP) accounts for friction, pumping losses, and accessory drives. IMEP is typically measured using cylinder pressure transducers and P-V diagrams.