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The Australian Standard - Methods of test for fuel consumption of passenger cars, their derivatives and multipurpose passenger cars, AS2077-1982 - is based on the method of determining petrol consumption accepted by the United States Environmental Protection Agency. In addition to volumetric and gravimetric fuel measurement techniques, the Standard also allows for the carbon balance method to be used to calculate fuel consumption from exhaust gas analysis data for a vehicle simulating city and highway driving conditions on a chassis dynamometer. Comparison of carbon balance fuel consumption results with data from a fuel flow meter fitted to the vehicle during tests, has shown consistent differences. Fuel consumption from the carbon balance method for hot start city cycle tests averaged 7% lower than volumetric results and 4% lower for the highway cycle.

A procedure has been developed for evaluating equivalent drive cycle emission results from raw exhaust gas emissions data obtained from an engine under test on a computer controlled Vehicle Simulator Engine Dynamometer. The emitted species data is integrated with the air intake flow rate to determine the total mass of emissions, after correcting for the reduction in exhaust gas mass due to precipitation of the moisture of combustion. This procedure eliminates the need for the Constant Volume Sample (CVS) System attached to the vehicle exhaust while undergoing simulated drive testing on a chassis dynamometer to evaluate compliance of the test vehicle with the Australian Design Rules, ADR27 and ADR37. Sources of error with the procedure are examined by comparing the fuel consumption measured using a volumetric technique during the test with that evaluated by a carbon balance procedure as given in the Australian Design Rules.