View Single Post
Old 08-05-2009, 02:39 AM   #49 (permalink)
Christ
Moderate your Moderation.
 
Join Date: Nov 2008
Location: Troy, Pa.
Posts: 8,919

Pasta - '96 Volkswagen Passat TDi
90 day: 45.22 mpg (US)
Thanks: 1,369
Thanked 430 Times in 353 Posts
Quote:
Originally Posted by MadisonMPG View Post
Is engine braking more fuel efficient than regular brakes?
Is that a serious question?

Brakes convert forward motion to heat, while allowing the engine to idle. In essence, you're burning fuel to slow down.

In FI cars, the ECU cuts fuel at a given RPM when there is no throttle input, which means you're slowing down/maintaining speed, but NOT burning ANY fuel at all. As soon as you touch the accelerator again, you're now spraying fuel, and you're capable of accelerating without problems.

In carb'd cars, this isn't the case, except where aftermarket modification has been made to shut off fuel inlet to the jets from the bowl when there is no throttle.
__________________
"¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"

  Reply With Quote