{"data":{"id":"us/40-cfr-appendix-ii-to-part-600","jurisdiction":"us","citation":"40 CFR Appendix II to Part 600","heading":"Appendix II to Part 600—Sample Fuel Economy Calculations","body":"(a) This sample fuel economy calculation is applicable to 1978 through 1987 model year automobiles.\n(1) Assume that a gasoline-fueled vehicle was tested by the Federal Emission Test Procedure and the following results were calculated:\nHC = .139 grams/mile\nCO = 1.59 grams/mile\nCO2 = 317 grams/mile\nAccording to the procedure in § 600.113-78, the city fuel economy or MPGc, for the vehicle may be calculated by substituting the HC, CO, and CO2 grams/mile values into the following equation.\nMPGc = 27.7\n(2) Assume that the same vehicle was tested by the Federal Highway Fuel Economy Test Procedure and calculation similar to that shown in paragraph (a) by this appendix resulted in a highway fuel economy or MPGh of 36.9. According to the procedure in § 600.113, the combined fuel economy (called MPGc/h) for the vehicle may be calculated by substituting the city and highway fuel economy values into the following equation:\n(b) This sample fuel economy calculation is applicable to 1988 and later model year automobiles.\n(1) Assume that a gasoline-fueled vehicle was tested by the Federal Emission Test Procedure and the following results were calculated:\nHC = .139 grams/mile.\nCO = 1.59 grams/mile.\nCO2 = 317 grams/mile.\n(2) Assume that the test fuel used for this test had the following properties:\nSG = 0.745.\nCWF = 0.868.\nNHV = 18,478 Btu/lb.\n(3) According to the procedure in § 600.113-08, the city fuel economy or MPGc, for the vehicle may be calculated by substituting the HC, CO, and CO2 gram/mile values and the SG, CWF, and NHV values into the following equation:\nMPGc = (5174 × 10 4 × CWF × SG) / [((CWF × HC) + (0.429 × CO + (0.273 × CO2)) ((0.6 × SG × NHV) + 5471)]\nExample:\nMPGc = (5174 × 10 4 × 0.868 × 0.745) / [(0.868 × .139 + 0.429 × 1.59 + 0.273 × 317)(0.6 × 0.745 × 18478 + 5471)]\nMPGc = 27.9\n(4) Assume that the same vehicle was tested by the Federal Highway Fuel Economy Test Procedure and a calculation similar to that shown in (b)(3) of this section resulted in a highway fuel economy of MPGh of 36.9. According to the procedure in § 600.210-08(c) or § 600.210-12(c), the combined fuel economy (called MPGcomb) for the vehicle may be calculated by substituting the city and highway fuel economy values into the following equation:","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER Q—ENERGY POLICY","PART 600—FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"addb9ea26fa51346b3fda69b0f8eead41a990c324e5a08860ebd2e04c699eb4a","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-appendix-i-to-part-600","next":"us/40-cfr-appendix-iii-to-part-600"},"notice":"GroundRules: Original legal text. Not legal advice."}