It is currently Thu Mar 28, 2024 1:43 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 29 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Windows Open VS Air
PostPosted: Sat Sep 10, 2005 4:28 pm 
Offline
LOST Newbie
User avatar

Joined: Sat Sep 10, 2005 4:23 pm
Posts: 11
Location: Canada
I'm a relatively new Liberty owner, and I’ve been reading these boards for some time now. An amazing amount of information is sitting in these boards for a “newbie” like myself.

With the price of fuel around 1.30 CDN a litre I am watching my driving very closely. I have wondered something since I got my new wheels; what is better for better mileage, windows open, or air conditioner on. And does this “formula” change if I’m driving in the city or on the highway.

_________________
Robert
http://www.robertlitchfield.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 10, 2005 5:54 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 12:31 am
Posts: 1979
Location: Lower NY
In 30+ yrs of driving I can tell u most assuredly that the drag on the engine from the ac drastically reduces mpgs. Next time u accelerate up a ramp cut off ure ac and watch the little extra burst of power u get. Any clutch running off the motor is gonna reduce your horsepower output. Car enthusiasts will tell u the best way to gain horsepower is to remove all items that run off the engine belts.

_________________
My pics!!
'03 Rennie w/all Tupperware
Custom Roof Basket
Mopar Tubular Brush Guard
Garmin GPS V & Laptop w/Nav software
RAM products laptop mount
Maglite w/mount
Rear cargo bay tool cabinet
AllJs Rear Shelf
Rear receiver
250k miles!
LOST #CR051230


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 10, 2005 8:06 pm 
Offline
LOST Newbie
User avatar

Joined: Sat Sep 10, 2005 4:23 pm
Posts: 11
Location: Canada
Cacher123, so your telling me it is better to drive with the windows open then with the AC on...interesting...

_________________
Robert
http://www.robertlitchfield.com


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 10, 2005 8:38 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 10:00 am
Posts: 119
Location: Alberta
Don't you guys ever watch Mythbusters? :)

At highway speeds - AC is more efficient.

In the city - open your windows.

_________________
2002 Liberty Renegade
All J Superskid and boulderbars, Cobra 75 CB and 2' Wilson, Garvin Wilderness rack, Frankenlift, BFG AT KO 245/75/16


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 10, 2005 9:25 pm 
Offline
LOST Member
User avatar

Joined: Mon Jul 11, 2005 12:29 am
Posts: 461
Location: Michigan
m0th wrote:
Don't you guys ever watch Mythbusters? :)

At highway speeds - AC is more efficient.

In the city - open your windows.


I LOVE THAT SHOW!! You are right BTW. I have learned so much watching that show. My wife ran throught the parking lot into work the other day and told me her clothes got really wet as a result. I laughed and told her shoe should have walked and she would have dryer clothes. I love Mythbusters.

_________________
2005 Unlimited (LJ) Rubicon w/ 5.5" of total lift
Flat Fenders made by http://www.jpfaboffroad.com/

"Democracy is two wolves and a lamb voting on what to have for lunch.
Liberty is a well-armed lamb contesting the vote." - Benjamin Franklin, 1759


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 10, 2005 9:58 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 12:31 am
Posts: 1979
Location: Lower NY
Quote:
I LOVE THAT SHOW!! You are right BTW. I have learned so much watching that show. My wife ran throught the parking lot into work the other day and told me her clothes got really wet as a result. I laughed and told her shoe should have walked and she would have dryer clothes. I love Mythbusters.

Was it raining at the time? Oh, and I like Buster!

_________________
My pics!!
'03 Rennie w/all Tupperware
Custom Roof Basket
Mopar Tubular Brush Guard
Garmin GPS V & Laptop w/Nav software
RAM products laptop mount
Maglite w/mount
Rear cargo bay tool cabinet
AllJs Rear Shelf
Rear receiver
250k miles!
LOST #CR051230


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 11, 2005 11:02 am 
Generally, I drive with the ac on and my drivers window open unless it's like 100 degrees w/ high humidity.


Top
  
 
 Post subject:
PostPosted: Sun Sep 11, 2005 11:40 am 
Offline
LOST Member
User avatar

Joined: Mon Jul 11, 2005 2:22 pm
Posts: 128
Location: Memphis, TN
as a summer-lovin redneck, I almost never use a/c (even at 100 & 100%). I can't say that my mileage has been affected by it, but note that most new vehicles are designed to drive at highway speeds with the windows up. This implies that the a/c (or vent) would be running. something to consider...

grant

_________________
"A well-crawled rock gathers no moss"

07 Ram 1500 RST 5.7L LOST #584737
Regency Custom Pkg - Black leather with red baseball stitching, 22" Foose "Speedster" wheels & Pirelli Scorpions, Brushed Aluminum gauges, roll pan, dual exhaust, lowered sport-tuned suspension, 4W Baers, BedRug, power everything
http://www.cardomain.com/profile/ltwgs


Top
 Profile  
 
 Post subject: I have to call bullsh*t on this one
PostPosted: Sun Sep 11, 2005 11:42 am 
Offline
LOST Newbie

Joined: Tue Aug 09, 2005 11:47 am
Posts: 38
Real highways have hills. Hills demand power. AC eats power directly at the drive belt. Enough said.

_________________
LOST Mid-Atlantic #071463
-----------------------------------
2K5 3.7L Sport in Patriot Blue w/ bug deflector
+ slush mats + JVC 12 Disc changer and HU
---------------
Coming Eventually:
Custom built fiberglass enclosure with two 12" 1000W DHD subs and one 12" 400W Orion sub with an 1800W Legacy amp and a 600W Boss amp


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 11, 2005 4:19 pm 
Offline
LOST Newbie
User avatar

Joined: Sat Sep 10, 2005 4:23 pm
Posts: 11
Location: Canada
Interesting...so from now on...highway is for AC and city will have windows open. Of course, living in Canada, this only applies to part of the year....the other part....windows closed and the heat CRANKED!!

_________________
Robert
http://www.robertlitchfield.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 11, 2005 4:30 pm 
Your not the only ones! :evil:


Top
  
 
 Post subject:
PostPosted: Mon Sep 12, 2005 8:48 am 
Offline
LOST Newbie

Joined: Thu Jul 28, 2005 10:20 pm
Posts: 78
Location: Tampa Florida
It's simply a matter of speed.

At lower speeds (below 50 mph) the increase in HP from the air being turned off outweighs the additional drag from the windows being down. Above the ~50 mph mark, the drag from the windows being open outweighs the power loss of the Air Conditioning being turned on.

Just got back from a weekend trip out of town... about 3/4 highway mileage this weekend with the majority of that being on the Interstate cruising with the windows up and the air turned on at the whopping speed of right around 63 mph... results:

388.1 miles on 18.01 gallons (tank filled to the top of the filler each time) = 21.5 mpg. Not Bad... especially for a 3.7L gas engine carrying the family and a fair load of gear aboard.

Luis

_________________
2005 Silver Liberty Renegade Rocky Mountain Edition 4x4 with Tow Pkg, Trac-Loc. Have had CJ5, CJ7, and a '99 TJ.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 12, 2005 9:19 am 
Offline
Lifetime Member
Lifetime Member

Joined: Thu Jul 07, 2005 7:01 pm
Posts: 1214
http://www.edmunds.com/ownership/drivin ... sonly..4.*

Intresting this article say the oposite, but they where only going 65mph and probably not much of a head wind. If the speed was raised to 70mph it might be different. Either way it is worth the comfort.


Top
 Profile  
 
 Post subject: Re: I have to call bullsh*t on this one
PostPosted: Tue Sep 13, 2005 10:25 am 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 10:54 am
Posts: 1115
Location: Inwood West Virgina
freetolio wrote:
Real highways have hills. Hills demand power. AC eats power directly at the drive belt. Enough said.

Real hi-ways have hills sometimes: not one big hill

_________________
"CHROME DON'T GET YOU HOME" "Just because I don't care dosen't mean I don't understand" Homer J. Simpson
Image
Webshots


Top
 Profile  
 
 Post subject:
PostPosted: Tue Sep 13, 2005 1:19 pm 
Offline
Lifetime Member
Lifetime Member

Joined: Wed Jul 27, 2005 2:46 pm
Posts: 1049
Location: Hermitage, PA
m0th wrote:
Don't you guys ever watch Mythbusters? :)

At highway speeds - AC is more efficient.

In the city - open your windows.

Right! what m0th said.

_________________
-nate
LOST#NL068123 - 2005 Renegade 3.7L 4x4, Off-Road Package, Rock Rails, Skids, Command-Trac, Trac-Loc LSD, Light Bar, K&N Drop in Filter, AMSOIL LUBES, RRO's Diff Guard for 8.25", Frankenlift, & Goodyear MT/R's
Cardomain


Top
 Profile  
 
 Post subject: AC vs Windows
PostPosted: Wed Sep 14, 2005 1:01 am 
Offline
LOST Newbie

Joined: Tue Aug 09, 2005 11:47 am
Posts: 38
http://www.treehugger.com/files/2005/06 ... or_d_1.php

The typical mileage gain of "windows down/AC off mode" is a few percent for a sedan but can range as high as 10% for trucks and SUV's (see graphic for SUV example).

in the graph 110 kph is around 68 mph, and significantly less gas usage is achieved by using windows instead of AC


I tend to believe GM engineers doing SAE tests over the mythbusters.

_________________
LOST Mid-Atlantic #071463
-----------------------------------
2K5 3.7L Sport in Patriot Blue w/ bug deflector
+ slush mats + JVC 12 Disc changer and HU
---------------
Coming Eventually:
Custom built fiberglass enclosure with two 12" 1000W DHD subs and one 12" 400W Orion sub with an 1800W Legacy amp and a 600W Boss amp


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 2:06 am 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 10:00 am
Posts: 119
Location: Alberta
Personally the reason I run the AC at highway speeds has nothing to do with whether it's more efficient, it's the noise. :)

And mentioning the Mythbusters thing was a joke BTW. From memory, the difference they found was minimal, and they were only testing at one fairly low speed.

_________________
2002 Liberty Renegade
All J Superskid and boulderbars, Cobra 75 CB and 2' Wilson, Garvin Wilderness rack, Frankenlift, BFG AT KO 245/75/16


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 16, 2005 2:07 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Fri Jul 08, 2005 2:34 pm
Posts: 680
Location: Cary, NC
If it's not humid out, I drive with the windows down. I haven't seen much difference. Of course, that's back when I had MTR's on. I'll have to compare the difference with the new road tires I put on.

I did build a custom shelf in the back that prevents the air from going down into the trunk cavity. The shelf prevents the helicopter buffetting noise and may help with the drag, but probably not much.

I would like to be able to replace the rear quarter windows with minivan style quarter windows to allow for the air to vent out the back.

_________________
O||||||O '04 Renegade L.O.S.T. #DL050292 - Life Time
Carolina L.O.S.T. Board of Directors
*** Stuff ***
CRS-Rock Rails * Rusty's Lift * *MTR's * Husky Mats * The 'Grill' and Shelf

FRS/CB (ch 6)


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 26, 2005 4:57 pm 
Offline
LOST Newbie

Joined: Thu Jul 28, 2005 10:20 pm
Posts: 78
Location: Tampa Florida
Tightwadsjeeper wrote:
It's simply a matter of speed.
At lower speeds (below 50 mph) the increase in HP from the air being turned off outweighs the additional drag from the windows being down. Above the ~50 mph mark, the drag from the windows being open outweighs the power loss of the Air Conditioning being turned on.
Just got back from a weekend trip out of town... about 3/4 highway mileage this weekend with the majority of that being on the Interstate cruising with the windows up and the air turned on at the whopping speed of right around 63 mph... results:
388.1 miles on 18.01 gallons (tank filled to the top of the filler each time) = 21.5 mpg. Not Bad... especially for a 3.7L gas engine carrying the family and a fair load of gear aboard.
Luis


Turns out I was somewhat mistaken... the difference DOES weigh in favor of windows down and AC off until the speeds become much higher (~80+?) and the drag of the windows being down surpasses the HP loss of the engine to the compressor.

My last highway trip was 318.3 miles using 13.244 gallons of gas doing 60 mph with the windows down and resulted in 24 MPG.

Luis[/b]

_________________
2005 Silver Liberty Renegade Rocky Mountain Edition 4x4 with Tow Pkg, Trac-Loc. Have had CJ5, CJ7, and a '99 TJ.


Top
 Profile  
 
 Post subject: Re: Windows Open VS Air
PostPosted: Tue Sep 27, 2005 3:13 pm 
Offline
LOST Member
User avatar

Joined: Sun Aug 21, 2005 12:36 pm
Posts: 114
Location: Antigua and Barbuda
Open the back window at highway speeds it will cut down on the drag.
If you keep the back window closed it acts like a parachute.
Just kidding, never ride with the window open. close windows at highway speeds. Open at local speed so you can make cat calls at pretty Jeepettes.

Yes the A/c does drain power, but how often are you going up hill at 70mph?




rlitchfield wrote:
I'm a relatively new Liberty owner, and I’ve been reading these boards for some time now. An amazing amount of information is sitting in these boards for a “newbie” like myself.

With the price of fuel around 1.30 CDN a litre I am watching my driving very closely. I have wondered something since I got my new wheels; what is better for better mileage, windows open, or air conditioner on. And does this “formula” change if I’m driving in the city or on the highway.

_________________
It's not a car
It's not an SUV
It's not a truck
It's a JEEP!


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 29 posts ]  Go to page 1, 2  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 9 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group. Color scheme by ColorizeIt!
Logo by pixeldecals.com