It seems than at Fri, 5 Sep 2008 14:42:23 -0500, R wrote: > I still think that frontal area is not nearly so important as > other things. You said "for a particular drivetrain > efficiency" and I agree with that.
Frontal area time Cd equals air resistance. So just looking at Cd numbers is half the story. Your pickup may have the same Cd as a big truck with a flatbed trailer - the frontal area is _way_ different. I think engine efficiency is a bigger deal than most figure on. And it can very depending on engine speed - especially with a turbo. There are plenty of stories of OM617 turbos that get _better_ fuel efficiency at higher road speeds, probably because the engine speed got to a sweet spot. > I wonder about some of the numbers quoted below as well. I > have a difficult time believing that the Tucker from the 40's > is the equal of some of the current vehicles. It was without > doubt efficient for its time, but it is still a lump compared > to most of the new vehicles. Aerodynamics is not a new science. The airplanes of the 1930's are quite smooth. The modern advantage is we can model ideas inside a computer with _way_ less effort than a physical model and a wind tunnel. -- Philip _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
