Quick question about going down hills... - Page 2 - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 06-16-2006, 12:24 PM   #11
FE nut
 
diamondlarry's Avatar
 
Join Date: Sep 2005
Posts: 1,020
Country: United States
Quote:
Originally Posted by 90CivicStandard
As I've been thinking about this I've come up with another question.

If the injectors aren't squirting any fuel while going down hill in gear, then wouldn't that negate the need to turn the car off? If it uses zero fuel either way then why would you need to turn the car off? Why not just leave it in a high gear like 5th where there is very little resistance?
Again, it really depends on the hill and the situation. If you need maximum coasting distance for say, going up another hill to get to the next downhill stretch, you would want to leave the car out of gear. If there is a known stop at the bottom and you know you can reach that stop, then leaving it in gear and using the engine instead of the brakes would be better.
__________________

__________________
Horsepower is how hard you hit the wall, torque is how much of the wall you take with you.

2007 Prius,



Team Slow Burn
diamondlarry is offline   Reply With Quote
Old 06-17-2006, 10:23 PM   #12
Registered Member
 
GasSavers_Ryland's Avatar
 
Join Date: Mar 2006
Posts: 1,325
Country: United States
Send a message via AIM to GasSavers_Ryland
I've been wondering the same thing about coasting and fuel useage, and have even thought about adding a lean burn carburator bypass valve to my motorcycle for coasting.
I also wonder if the EGR valve opens while coasting, so it woudl keep the engine warmer.
I can tell from expearince that even in 5th gear, you slow down a bit with your foot off the gas, altho on hilly streaches of highway I've been able to stay above 65mph, and do coasting like this, and it's hard to tell exactly how much it has helped as I've done some other work recently as well, but it seems to give up to a 4-5mpg boost over compleat foot on gas driving, and nertral engine on coasting.
__________________

GasSavers_Ryland is offline   Reply With Quote
Old 06-18-2006, 12:21 PM   #13
Registered Member
 
Join Date: Apr 2006
Posts: 228
Country: United States
I have been trying the EOC on long decents to gain max momentum. The EOC feels dangerous the first few times you try it (so do it in a very safe place). After that it gets easier, and I am now comfortable with the technique of letting out the clutch in 5th to spin the engine and recharge the brake vacuum. It seems that this is the best tank ever, including some driving in the rain with 2 passengers, and some dirt road driving...+-46MPG (fuel guage estimate) in the 89 toyota camry 5spd.
GasSavers_James is offline   Reply With Quote
Old 06-20-2006, 12:44 AM   #14
Registered Member
 
Join Date: May 2006
Posts: 78
Country: United States
Quote:
Originally Posted by thisisntjared
actually the vacuum helps the the crank side of the cylinders as there is less air to push out of the way.
No air to push out of the way. It balances out as one pistons goes down another comes up. However, closed throttle coasting with high vacuum can cause more oil to be sucked by the rings and the valve guides. Especially bad in high milage engines. oil in the combustion chamber leads to carbon build up.
__________________
Kevin A Thornton
KAT Automotive
For Speed Equipment, Nitrous Express
katman@everestkc.net

For AMSOIL products
http://www.lubedealer.com/kat

For Herbs from the Amazon
http://www.168336.amazonherb.net
GasSavers_katman is offline   Reply With Quote
Old 06-20-2006, 03:31 AM   #15
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
gear or neutral

A little oil past the rings can be a good thing too. In my xB the fuel is still being injected and more is injected if the revs get too high - over 2000rpm I think it burns more - it is supposed to be open loop - when the engine is cool I can feel the extra gas kick in as the braking action is reduced suddenly. I put it in neutral like when I go over the Sakonnet River Bridge taking the exit on the bridge to go south I can coast 1 mile to the Stone Bridge which when you look back is an amazing distance. Only thing else is if it is hot out and the engine is turning faster the water cools better and if you are running the AC then crank up the blower and get some of the energy converted into cold as well as crank up the alternator.
JanGeo is offline   Reply With Quote
Old 06-20-2006, 04:42 AM   #16
Registered Member
 
psyshack's Avatar
 
Join Date: May 2006
Posts: 443
Country: United States
Throw it in N, shut the engine off, roll key back to ing. II and enjoy the ride.
__________________
09 HCHII, w/Navi
07 Mazda3 S Touring, 5MT
Mild Hypermiler or Mad Man?
psyshack is offline   Reply With Quote
Old 06-20-2006, 04:00 PM   #17
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
xB will not turn for anything if the engine is not pumping the power steering. I did roll a few feet today with the engine off and the SGII read 9999mpg.
JanGeo is offline   Reply With Quote
Old 06-20-2006, 04:03 PM   #18
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
Factory manual steering strikes again! Mwahaha.
SVOboy is offline   Reply With Quote
Old 06-20-2006, 04:18 PM   #19
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
Quote:
Originally Posted by SVOboy
Factory manual steering strikes again! Mwahaha.
I could motorize it with electric because it runs on a separate belt but I can live with it - nice to be able to turn corners on two wheels like I was doing today - that takes some assist. I am not worried about 0.1-0.2 gallons per hour.
__________________

JanGeo is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Two stroke oil in diesel Eybrows General Fuel Topics 16 01-27-2013 09:20 PM
Suggestions needed Matt Timion Fuelly Web Support and Community News 80 03-28-2009 06:37 AM
Fuelly for international? pixelthing Fuelly Web Support and Community News 8 08-11-2008 08:32 AM
Garage/Gas-Log Trend? 95metro General Discussion (Off-Topic) 27 07-13-2006 10:24 AM
I issue a challenge!!! Matt Timion General Discussion (Off-Topic) 32 01-29-2006 06:28 PM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 04:30 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.