Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Shift points: EPA testing of manual transmissions (why beating MT ratings is easier)

B440 · 11-01-2013, 01:59 PM

Some interesting points:

"The EPA has a specialized company manufacture small batches of consistent fuel, which is 93 octane (cars running 50-state certifications get a slightly different, 91-octane “California” blend)." <--and no mention of 10% ethanol

"The EPA tested the M5 in both 400- and 500-hp modes and found no difference in the amount of fuel used. The demands of the test cycles never call upon all the M5’s horses anyway. And the Honda Insight’s econ mode—activated by a dash button and claimed to improve fuel economy—registered no effect, either. It relaxes throttle response, so the test driver simply compensates with additional throttle to achieve the required speeds. However, GM’s skip-shift device, found in the Corvette among others, irritates by forcing the driver to shift the manual transmission from first gear to fourth at low speeds and was developed precisely to improve fuel economy on the test cycles. It was approved by the EPA, i.e., not considered cheating."

"In 1998, all the major players in heavy-duty diesels (Caterpillar, Cummins, Detroit Diesel, Mack Trucks, Navistar, Renault, and Volvo) were cited for an engine-control strategy that leaned out the air-fuel ratio at steady highway speeds, which boosted fuel economy at the expense of NOx emissions. The EPA slapped those seven manufacturers with what it called the “largest civil penalty in environmental enforcement history,” a total of $83.4 million in fines." <--So this and other posts I've read on here basically lead me to believe that "lean-burning" is an easy and excellent way to save fuel, but raises NOx emissions, so automakers barely implement it?

"Don’t even think of comparing EPA figures with stand*ardized fuel-economy tests from other countries because the test cycles are very different. For example, the European highway rating, called “extra urban,” is higher than the EPA’s by about 30 percent, so a rating on that cycle of, say, 60 mpg, would be closer to 40 in this country. The mainstream press, not realizing the difference, often complains that automakers refuse to bring efficient models here when, in fact, they may not be all that efficient when measured by U.S. standards." <--Euro cars can get 75+mpg. Even dropping that down to U.S. mpgs would still be better than most cars sold in the USA.

11-01-2013, 01:59 PM	#11 (permalink)
B440 EcoModding Lurker Join Date: Oct 2013 Location: Thompson, CT Posts: 32 none - '15 Mazda CX-5 Sport Thanks: 4 Thanked 5 Times in 4 Posts	Some interesting points: "The EPA has a specialized company manufacture small batches of consistent fuel, which is 93 octane (cars running 50-state certifications get a slightly different, 91-octane “California” blend)." <--and no mention of 10% ethanol "The EPA tested the M5 in both 400- and 500-hp modes and found no difference in the amount of fuel used. The demands of the test cycles never call upon all the M5’s horses anyway. And the Honda Insight’s econ mode—activated by a dash button and claimed to improve fuel economy—registered no effect, either. It relaxes throttle response, so the test driver simply compensates with additional throttle to achieve the required speeds. However, GM’s skip-shift device, found in the Corvette among others, irritates by forcing the driver to shift the manual transmission from first gear to fourth at low speeds and was developed precisely to improve fuel economy on the test cycles. It was approved by the EPA, i.e., not considered cheating." "In 1998, all the major players in heavy-duty diesels (Caterpillar, Cummins, Detroit Diesel, Mack Trucks, Navistar, Renault, and Volvo) were cited for an engine-control strategy that leaned out the air-fuel ratio at steady highway speeds, which boosted fuel economy at the expense of NOx emissions. The EPA slapped those seven manufacturers with what it called the “largest civil penalty in environmental enforcement history,” a total of $83.4 million in fines." <--So this and other posts I've read on here basically lead me to believe that "lean-burning" is an easy and excellent way to save fuel, but raises NOx emissions, so automakers barely implement it? "Don’t even think of comparing EPA figures with stand*ardized fuel-economy tests from other countries because the test cycles are very different. For example, the European highway rating, called “extra urban,” is higher than the EPA’s by about 30 percent, so a rating on that cycle of, say, 60 mpg, would be closer to 40 in this country. The mainstream press, not realizing the difference, often complains that automakers refuse to bring efficient models here when, in fact, they may not be all that efficient when measured by U.S. standards." <--Euro cars can get 75+mpg. Even dropping that down to U.S. mpgs would still be better than most cars sold in the USA.