Go Back   EcoModder Forum > EcoModding > Hypermiling / EcoDriver's Ed
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 08-08-2012, 05:34 AM   #21 (permalink)
wdb
lurker's apprentice
 
Join Date: May 2008
Location: the Perimeter
Posts: 942

PlainJane - '12 Toyota Tacoma Base 4WD Access Cab
90 day: 20.98 mpg (US)
Thanks: 504
Thanked 226 Times in 173 Posts
Quote:
Originally Posted by Old Mechanic View Post
Coasting in gear is not really coasting, since there is engine braking involved unless clutch disengaged in a manual).
Is that still as true as it used to be, this far along the trajectory of Moore's Law? My wife's 2011 CRV (they only sell them as automatics) rolls out pretty far in gear, when I'm moving at speed on a flat road; it doesn't quite feel like it's in neutral, but there is minimal engine braking taking place. When going downhilll however, I can really feel the engine braking the vehicle. I attribute the difference to Honda's transmission management logic.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 08-08-2012, 09:45 AM   #22 (permalink)
EcoModding Lurker
 
Join Date: Dec 2011
Location: United States
Posts: 36

RebCivic - '12 Honda Civic EX
Thanks: 4
Thanked 4 Times in 3 Posts
Quote:
Originally Posted by wdb View Post
Is that still as true as it used to be, this far along the trajectory of Moore's Law? My wife's 2011 CRV (they only sell them as automatics) rolls out pretty far in gear, when I'm moving at speed on a flat road; it doesn't quite feel like it's in neutral, but there is minimal engine braking taking place. When going downhilll however, I can really feel the engine braking the vehicle. I attribute the difference to Honda's transmission management logic.
I don't understand the point you're trying to make. You start by questioning whether engine braking is occurring (and why is Moore's law relevant?), and then go on to describe you actually do observe it occurring. Seems to me you've answered your own question.
__________________
  Reply With Quote
Old 08-08-2012, 10:52 AM   #23 (permalink)
Master EcoModder
 
Join Date: Jan 2011
Location: na
Posts: 1,025
Thanks: 277
Thanked 218 Times in 185 Posts
Automatics tranny engine braking depends on the car. Neither of my GM auto coast hardly any different OD or N. If engine braking is wanted need to put them in D or 2. Stratus engine brakes and downshift and brakes even more, so it needs to be shifted to N to coast well.

I wonder if the CRV is it keeping it's torque convertor locked going down hill to avoid speeding up. But unlocks it when coasting as long as not gaining speed.

The stratus if cruise is set and go down a hill large enough for it to pickup speed, will disconnect the tranny, the engine revs to 3,000 rpm, waiting for the car to get back down to the set point where the tranny will reengage, on hills that I know it will do it I will cancel cruise, shift to N, and then reengage tranny & cruise once the coast if over.
  Reply With Quote
Old 08-08-2012, 11:19 AM   #24 (permalink)
Hydrogen > EV
 
Join Date: Apr 2012
Location: NW Ohio, United States
Posts: 2,022

Silver Flea - '05 Honda Insight
90 day: 58.96 mpg (US)
Thanks: 992
Thanked 396 Times in 283 Posts
Quote:
Originally Posted by jsatter View Post
You have to be on the gas longer to reach a coast point too. You lose on both ends when you coast in gear.
I disagree with this. But only at certain speeds. When I go to the cemetary near me, I park on top of a hill. The scAngauge resets, and I roll forward and bump start into first, go to second and third, going back up the hill on the other side, she needs second, but by time I am out I get to almost 30 mph, 33-35 mpg, and use zero throttle pedal. Now I don't kow how much fuel I use, but it must be minimal, I put it into gear at 4xx rpm range and she wants to climb back up.

So for me, in THIS case, in gear coasting is very beneficial. Or maybe it's not technically coasting since I start at a stop. If this is the highway we are talking, then hands down, I totally agree. But unless I am 30+ mph, going uphill, or can see my stop point, I (think) I am better off in gear.

But those are strict standards. So I can happily agree usually out of gear coasting is more efficient than in gear.
__________________





Best Tanks:
Mustang - 54.83 mpg (US) at the Green Grand Prix
Insight - 82.91966 mpg (US) over 818.5 miles.
  Reply With Quote
Old 08-08-2012, 11:51 AM   #25 (permalink)
Drive less save more
 
ecomodded's Avatar
 
Join Date: Jul 2011
Location: Vancouver Island, Canada
Posts: 1,189

Dusty - '98 VOLKSWAGEN Beetle TDI
TEAM VW AUDI Group
90 day: 60.42 mpg (US)
Thanks: 134
Thanked 162 Times in 135 Posts
Coast down a secluded hill from a set starting point, till you reach a stop,mark the spot. Repeat it in neutral , repeat it all again. Then crunch the numbers.
__________________
Save gas
Ride a Mtn bike for errands exercise entertainment and outright fun
__________________



  Reply With Quote
Old 08-08-2012, 12:04 PM   #26 (permalink)
Rat Racer
 
Fat Charlie's Avatar
 
Join Date: May 2011
Location: Route 16
Posts: 4,150

Al the Third, year four - '13 Honda Fit Base
Team Honda
90 day: 42.9 mpg (US)
Thanks: 1,784
Thanked 1,922 Times in 1,246 Posts
UltArc- Sorry, I wasn't trying to get in your face too much. But I was really hoping that you were joking in your hope that ksa8907 was joking.

To the challenge of "Find me some numbers," The only real answer here is "I can't." It can't realistically be tested for. The sheer obvoiusness of riding the brakes being bad for FE really turns the question around: Don't ask me to explain the benefits of coasting in neutral, explain to me why you think staying in gear is better than popping it into neutral.
__________________

Quote:
Originally Posted by sheepdog44 View Post
Transmission type Efficiency
Manual neutral engine off.100% @MPG <----- Fun Fact.
Manual 1:1 gear ratio .......98%
CVT belt ............................88%
Automatic .........................86%

  Reply With Quote
Old 08-08-2012, 04:05 PM   #27 (permalink)
EcoModding Lurker
 
Join Date: Mar 2012
Location: Earth
Posts: 27

Breeze - '97 Plymouth Breeze
90 day: 23.1 mpg (US)
Thanks: 2
Thanked 16 Times in 8 Posts
Quote:
Originally Posted by ecomodded View Post
Coast down a secluded hill from a set starting point, till you reach a stop,mark the spot. Repeat it in neutral , repeat it all again. Then crunch the numbers.
In neutral is essentially guaranteed to coast further but proves nothing. The real test would be to see if the extra fuel needed to idle the engine while in neutral is /less/ then the fuel saved by driving the engine with the transmission in gear.
  Reply With Quote
Old 08-08-2012, 04:18 PM   #28 (permalink)
Master EcoModder
 
Join Date: Sep 2009
Posts: 5,927
Thanks: 877
Thanked 2,024 Times in 1,304 Posts
Coast in neutral, at 70 MPH, down a 5% grade on the Interstate (in neutral which is the DEFINITION of coasting) with a tractor trailer on yer butt, then shove it in gear and see what happens.

regards
Mech
  Reply With Quote
Old 08-08-2012, 05:28 PM   #29 (permalink)
Hydrogen > EV
 
Join Date: Apr 2012
Location: NW Ohio, United States
Posts: 2,022

Silver Flea - '05 Honda Insight
90 day: 58.96 mpg (US)
Thanks: 992
Thanked 396 Times in 283 Posts
Quote:
Originally Posted by ecomodded View Post
Coast down a secluded hill from a set starting point, till you reach a stop,mark the spot. Repeat it in neutral , repeat it all again. Then crunch the numbers.
I hope I remember to test this next week! I am rather curious about this now. At first, for MY situation, I thought it almost for sure, but really breaking it down, I don't know. I normally bump start my engine, next time I won't, so it stays fair. I think in neutral there will be a lot more variables in play. In gear it is smoother, but hopefully we'll see soon.

Quote:
Originally Posted by Fat Charlie View Post
UltArc- Sorry, I wasn't trying to get in your face too much. But I was really hoping that you were joking in your hope that ksa8907 was joking.

To the challenge of "Find me some numbers," The only real answer here is "I can't." It can't realistically be tested for. The sheer obvoiusness of riding the brakes being bad for FE really turns the question around: Don't ask me to explain the benefits of coasting in neutral, explain to me why you think staying in gear is better than popping it into neutral.
Honestly, I did take it as hostile, but being it all in text, and this being a friendly forum, I figured I just took it the wrong way. And maybe my comment seemed hostile, too, so I try not to take any offense from anything. No harm, no foul.

I see your point in that, but some people are not very open minded :/ They get an idea, and that is just so until proven otherwise. My family is very much stubborn in this way. For years I have been telling them to unplug chargers and tvs and whatever they don't use, as it drains power. They finally did it to shut me up, and now they must constantly unplug everything that is not theirs, because of the energy they save.

Even on here, I remember someone switched to a funnel air intake rather than stock on a Focus I believe, and did not do very scientific reporting. The response was not very friendly lol. I know now to watch my exhuast when I talk about FE numbers lol.
__________________





Best Tanks:
Mustang - 54.83 mpg (US) at the Green Grand Prix
Insight - 82.91966 mpg (US) over 818.5 miles.
  Reply With Quote
Old 08-08-2012, 06:29 PM   #30 (permalink)
EcoModding Lurker
 
Join Date: Dec 2011
Location: United States
Posts: 36

RebCivic - '12 Honda Civic EX
Thanks: 4
Thanked 4 Times in 3 Posts
Quote:
Originally Posted by RiceCake View Post
In neutral is essentially guaranteed to coast further but proves nothing. The real test would be to see if the extra fuel needed to idle the engine while in neutral is /less/ then the fuel saved by driving the engine with the transmission in gear.
That's why I wanted a net usage measure, not a measure of usage during the coast.

__________________
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com