View Single Post
Old 02-08-2010, 04:35 PM   #12 (permalink)
MetroMPG
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,515

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 52.48 mpg (US)
Thanks: 4,062
Thanked 6,959 Times in 3,603 Posts
Quote:
Originally Posted by greasemonkee View Post
The end result - more negative work applied to the reciprocating assembly, more wasted work than driving higher rpm. This is a general rule with 1000's of variables, but there is a window where your loading/rpm relationship yields the lowest bsfc. Finding that window is the hard part.
My experience: I've yet to find a car where (in real world circumstances) the best cruising fuel economy isn't in the highest gear possible without lugging. I don't think the "best" engine RPM/load window is hard to find.

At cruise, the rule of thumb is: upshift, unless it lugs.
__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote