The heating value or heat of combustion is a measure of the energy available from the fuel. The fraction or percentage of the heat of combustion that is converted to useful work is a measure of the thermal efficiency of an engine. Thus@ a knowledge of the heat of combustion of the fuel is basic to the engineering of automotive engines. This SAE Information Report provides information on the standardized procedures for determining the heat of combustion of fuels that may be used for automotive engines.RationaleThe changes to SAE J1498 include:Other Publications??ASTM Methods D 2015@ D 2163@ D 3286@ and E 380 have been withdrawn by ASTM. D 5865 has replaced D 3286 and SI 10 has replaced E 380. Eliminated reference to withdrawn standards. Volumes have been made correct.Section 4??Changed E 380 to SI 10.Section 9.1??Eliminated reference to D 2163 which has been withdrawn by ASTM. Renumbered test method list.Section 9.3??Eliminated reference to D 2015 and D 3286 which have been withdrawn by ASTM. Added D 5865 and renumbered test method list. Eliminated old Table 3 and replaced it with new one showing current test method precision.?