> =A0 Then it wouldn't be much of a hill and you wouldn't be coasting. The
> discusion was about coasting down hill.
REALLY?
You cannot COAST down a hill with the car in gear??? You WILL coast,
moron, albeit at a slower terminal velocity.
I have to ask 2 questions to everyone who has responded:
1) do you ****ing people even DRIVE a car
2) do you ****ing people THINK before you write this ****?
> =A0If the transmission is in neutral it is NOT coupled to the driveline
an=
d WILL
> be at idle speed.
Wow...REALLY? ****, I didn't know that.
I was answering a question in TWO PARTS, DO NOT CONFUSE THE TWO.
I was explaining WHY THE ENGINE WOULD NOT DROP TO IDLE WHILE IN GEAR.
> =A0 You save fuel because the injectors are shut off and NO fuel is
being
> delivered. What part of this don't you understand ?
Holy ****, you people are so mother****ing dense it is incredible.
The ****ing ISSUE IS NOT WHETHER I SAVE ****ING FUEL WHEN I AM NOT ON
THE MOTHER****ING GAS PEDAL, YOU IDIOT.
The ****ing ISSUE IS WHETHER I SAVE FUEL IN NEUTRAL VERSUS IN GEAR ON
ANY GIVEN DOWNGRADE.
MY ASSERTION IS THAT ON MANY DOWNGRADES YOU WIILL SAVE FUEL BY
****FTING TO NEUTRAL BECAUSE OVERCOMING ENGINE COMPRESSION REQUIRES
MORE ENERGY THAN IS BEING GIVEN TO THE CAR VIA GRAVITY.
AT HIGHWAY SPEEDS, YOU USE FUEL TO PHYSICALLY DRIVE DOWNHILL BECAUSE
COMPRESSION AT HIGHWAY RPMS IS RELATIVELY HIGH, and when it is
combined with drag it EXCEEDS the return from gravity.
Mother****ing this is SO EASY for you to test, why the **** are you
even HERE arguing with me about it?
ON ANY GRADE in which letting off the gas pedal causes you to slow,
but ****fting into neutral causes you to accelerate OR stay at the same
speed, the SOLE DECELERATION SUBTRACTED OUT IS ENGINE COMPRESSION.
> =A0 Correct. But as soon as you step on the accelerator the ECM turns
the
> injectors on and fuel usage resumes. So you use more fuel COASTING IN
GEAR=
> with your foot off the accelerator.
Look, man, I do not require you to comment or correct me on any of
this. I have no clue at what point you people diverged so ****ing
radically from what the POINT of the original discussion was, which
was that shutting the engine off and coasting in idle will usually
save MORE FUEL than maintaining a level speed on a downgrade because
MOST downgrades are inadequate to overcome the engine compression
commensurate with RPMs at highway speeds.
How this ****ing morphed into something else is BEYOND ME
> =A0 And you miss the point once again ! The question was "what uses more
f=
uel ,
> coasting downhill in neutral or in gear". =A0And the answer is coasting
in=
gear
> uses NO FUEL as the injectors are SHUT OFF in that situation
That was NOT THE QUESTION.
I AM THE ONE who made the ORIGINAL statement. Your issue of whether
the car consumes zero fuel while in-gear with zero throttle is
IRRELEVANT TO IT.
The REASON it is so is because the ****ing car STILL HAS TO OVERCOME
ENGINE COMPRESSION and if the grade is not steep enough, it WILL NOT
DO SO. Therefore, drag + compression losses will OVERCOME gravity
acceleration and I will LOSE SPEED when I wish to maintain it. In
THAT CASE, to maintain speed, I would have to consume MORE fuel than I
would by ****fting into neutral.
A hybrid like the Prius would actually shut the engine OFF. It does
this ALL THE TIME when you are on the highway going down a grade where
engine compression is material. If you are in cruise control, the car
will drag the regenerative brakes if the grade IS sufficient to
overcome drag.
You cannot go to zero throttle on EVERY freakin hill.
Trav
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