View Single Post
Old 08-12-2014, 08:09 AM   #6 (permalink)
sarguy01
Master EcoModder
 
sarguy01's Avatar
 
Join Date: Jan 2010
Location: Virginia Beach
Posts: 468

Mazda5 - '12 Mazda 5
90 day: 25.22 mpg (US)

Big D - '11 Dodge Durango Crew
90 day: 18.75 mpg (US)
Thanks: 86
Thanked 87 Times in 54 Posts
Quote:
Originally Posted by hertfordnc View Post
This may be a Cummins-specific question, The computer always provides enough fuel to keep it from stalling.

It idles at 700 RPM but when i am rolling along in 4th gear with my foot off the throttle it is turning around 1000 rpms. So it's burniong more fuel that it would idling at a stop.

The question is, does it burn more or less fuel than it would in a lower gear at a proper RPM?

Peak efficiency for this engine is around 1600 (peak torque)
Sounds like you should do some testing!! I don't know the details of the truck, but can you get some instrumentation to do some testing?
  Reply With Quote