If the motor idles at 6000 rpm it must be a gas turbine or something. On Feb 5, 2017 9:32 PM, "Scott Ritchey via Mercedes" <mercedes@okiebenz.com> wrote:
Food for thought: One reason Diesels are more efficient than gas engines is Diesels (mostly) don't have throttles. This is mainly a factor low speed and at idle: gas engine waste a LOT of power idling. Consider a 3 liter (183 CID) engine that idles at 6000 RPM. The intake manifold pressure would be near ambient for a Diesel but a gasoline engine would idle at a manifold vacuum of about 20 inches (10 PSI). So the energy required to turn the crank one full cycle (2 revs) would be 1830 inch-lbs or 152 ft-lbs. For 3000 full cycles per minute (6000 RPM), this is 457500 ft-lb of work per minute or 14 HP. So the hypothetical 3 liter gas engine must produce 14 HP while stopped at a traffic light just to keep the engine turning against manifold vacuum. Scott _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
