This paper reports on attempts to correlate measured oil flow rates for a big-end connecting rod bearing with those predicted by theory. The oil flow measurements were made on a 2.0 litre naturally aspirated gasoline engine. The theoretical predictions were made using an elastohydrodynamic model of the bearing system. This model used a finite difference solution technique, which incorporated a lubricant mass conservation algorithm. The measured bearing bore shape was used to give precise clearance data. Measured bearing temperature was used to calculate the effective operating viscosity. Locally refined mesh densities were used in the region of the relief bearing to improve accuracy. The correlation between experimental measurements and theoretical predictions has proved excellent, except at very high speed when theory tends to over-estimate the measured oil flow.