View Single Post
Old 03-24-2014, 06:13 PM   #11 (permalink)
Master EcoModder
jedi_sol's Avatar
Join Date: Mar 2009
Location: Tustin, CA
Posts: 929

2013 STi *SOLD* - '13 Subaru Impreza WRX STi
Sports Cars
Team Turbocharged!
90 day: 26.59 mpg (US)

1996 Geo Metro *RETIRED from Ecomodding* - '96 Geo Metro Base
90 day: 58.68 mpg (US)
Thanks: 368
Thanked 378 Times in 236 Posts
Originally Posted by bestclimb View Post
I think this has been tested (though not necessarily for a subaru with it's added AWD drag), leaving it in gear pulsing then coasting down in gear with dfco. from what I remember the coast downs were short enough that coasting in neutral with the engine idling was more efficient.

The wear from a bump start is pretty negligible given the forces involved. With a bump start you are getting the weight and drag of the moving parts of the engine going. Compared to just getting the car moving you are getting the whole mass of the vehicle moving.
Yes, in most cases, coasting in neutral is more efficient than coasting in gear/dfco because neutral coasts typically last longer.

My observation on my subaru (possibly other subaru's), when i shift to neutral and the rpms drop....around approximately 1000rpms, the fuel injectors cut off for a split second.

My theory is that when i am coasting in neutral, if i keep blipping the throttle around the 1000rpm sweet spot, i am able to coast in neutral while simulating Engine OFF coasting vs. coasting in straight neutral.


See the rest of the Sti project log:
  Reply With Quote