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Old 07-25-2008, 02:04 PM   #1
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AeroDynamics?

0k, so all jeep owner know that we have the least areodynamic car on the street. That is ok since it is a bad ass ride that people should bow to.

My question is, with consideration to the soft top, when is the wrangler most aerodynamic and therfor most fuel efficient?

I know that top on with windows down is the least aerodynamic.

So is the car the best on mpg when the windows are up or when the entire top if off?

I realize that these changes will on affect mpg by maybe 1/4 a mile, but here at the wrangler forum we must do everything we can during this droubt.

Liberals let us drill already!!!

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Old 07-25-2008, 02:25 PM   #2
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Top up and windows up is more aerodynamic and produces better mpg than with the top off. That, at least, according to a few articles I read some time back.

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Old 07-25-2008, 02:42 PM   #3
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Originally Posted by Jerry Bransford View Post
Top up and windows up is more aerodynamic and produces better mpg than with the top off. That, at least, according to a few articles I read some time back.
yeah, i recall reading the same. it gets best milage with a hardtop, windows on/ rolled up, and the worst mileage i believe was when there was no top... but hey, that's the most fun
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Old 07-25-2008, 02:46 PM   #4
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Aerodynamics???? I didnt even know we had those I like to go by the fun meter where the top down doors off method is always a winner.... unless its raining that is...
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Old 07-25-2008, 02:49 PM   #5
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What's funny is that trucks get better mileage with the tailgate up than when it's down. I can see the turbulance of no top affecting a Jeep but it just seems a tailgate being down would be better. But wind tunnel tests always confirm it's better with the tail gate up, that there is a 'bubble' that forms over the truck bed when the tailgate is up that smooths the air flow for better fuel economy. My buddy was an aerodynamics engineer, none of this would surprise him I guess.
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Old 07-25-2008, 03:13 PM   #6
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Aerodynamic VS Looking cool

Come on guys; who would not give up a few MPGs for the trade of Driving Topless?

I can only think of ONE THING I like more than driving my Jeep with the top down; doors off and PAT GREEN Cranked up loud!
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Old 07-25-2008, 03:36 PM   #7
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Hard top on and windows up is best, When i remove my doors and have the hard top on, my jeep is really "dying". You gotta ride the gas a lot to keep it going.

Windows up and ac on will also give you worse mpg so keep them windows down when you need to
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Old 07-25-2008, 03:46 PM   #8
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Originally Posted by Triple88a View Post
Windows up and ac on will also give you worse mpg so keep them windows down when you need to
Not true, that's an old wive's tale.
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Old 07-25-2008, 04:06 PM   #9
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Quote:
Originally Posted by Jerry Bransford View Post
Not true, that's an old wive's tale.
I burned quarter tank of gas in 50 miles with the ac on on the highway (55-60mph). I keep my windows down and no ac, i go easily over 60 miles on a quarter tank even in the city

The drag from the compressor is very noticeable especially on manual transmission vehicles.
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Old 07-25-2008, 04:50 PM   #10
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Originally Posted by Triple88a View Post
I burned quarter tank of gas in 50 miles with the ac on on the highway (55-60mph). I keep my windows down and no ac, i go easily over 60 miles on a quarter tank even in the city

The drag from the compressor is very noticeable especially on manual transmission vehicles.
Whatever Tripp...
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Old 07-25-2008, 04:53 PM   #11
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Whatever Tripp...
dont make me say it
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Old 07-25-2008, 05:12 PM   #12
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Old 07-25-2008, 05:16 PM   #13
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Congratulations Trip, you are the first person I have ever put on 'Ignore'... you're just like like a young puppy dog bouncing around looking for attention and too distracting. Don't bother replying, I won't see it.
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Old 07-25-2008, 05:18 PM   #14
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man the clear stuff is freaking expensive (my local store sells acrylic). I'll need like 40-50 bucks worth of the darn thing to make it work + the two 1/4th" rods to hold it to the front grill.

LoL.. it's all about the signal to noise ratio
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Old 07-25-2008, 10:50 PM   #15
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mythbusters tested the afore mentioned "myths"
mythbusters is a bunch of BS. they have no friggen common sense and over anylize they're incorrect answers, but hey everything is "plausible" right?
i had a 4 cyl toyota pickup while i was in Wyoming, driving down I-80(75 mph) i could only hit 65, pulled over and dropped the tailgate, voila! could drive the speed limit(though still barely) tell me MORE drag made it go faster.
same thing with the a/c, it takes a lot of power to turn that compressor, you can feel it moreso in an underpowered vehicle(read toyota), turn on the a/c at 75 mph and the truck would lose speed, roll down a window and everything was a/ok.
taking 2 different vehicles and driving them down the highway is no comparison, but that show states it as fact. "the one with the tailgate down ran out of gas first, so it must be false! "
the areodynamics of a jeep arent totally the cause(though wind resistance is the largest part of fuel economy), its the POS engine thats killing the mileage. just look at the JK's that are getting high teen/low 20 MPG's
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Old 07-26-2008, 12:39 AM   #16
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Sean, there is a reason why i'm in his ignore list now. Just read the posts above.
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Old 07-26-2008, 03:43 AM   #17
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haha i cant remember the last time i turned on the AC with these gas prices.
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Old 07-26-2008, 04:39 AM   #18
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Quote:
Originally Posted by sean42069 View Post
"the one with the tailgate down ran out of gas first, so it must be false!
you know they revisited that myth right? their conclusion was that the "net tailgate" gave them the best mpg's
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Old 07-26-2008, 04:40 AM   #19
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Congratulations Trip, you are the first person I have ever put on 'Ignore'...
we can ignore him ?

haha just playing trip !
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Old 07-26-2008, 11:19 AM   #20
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we can ignore him ?

haha just playing trip !
lol i was thinking of doing that but naaa hes way too funny to ignore especially when trying to put down people , i'm not saying he doesnt know his stuff, just many times he is full of himself.

just fyi, mythbusters are not very smart so dont believe everything they "prove" lol.
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Old 07-26-2008, 11:28 AM   #21
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my best tank of gas or trip, was with bestop half doors, bestop bikini and a ton of wheeling and camping gear in the back. i almost crack 18mpg at 5am going to barstow from orange county. I didnt believe it and had redid my math like 5 times. i think what matters most is having your motor and gears with good fluids with a fresh air filter. speaking of which time to go change the oil and take in for a smog run.
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Old 07-26-2008, 11:34 AM   #22
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the other day i filled up, i measured about 19 mpg in city.
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Old 07-26-2008, 03:55 PM   #23
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Barstow, now that brings back memories. In my Army days, stationed at Ft. Ord, CA, we used to go down there( Ft. Irwin) all the time for war games. Coldest & hottest place have ever been in my life. Drove for the Lt. so got to cruise all around the Mojave desert in a Humvee. Had a lot of fun driving it.
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Old 07-28-2008, 12:42 PM   #24
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I just returned back from a trip and managed to do some milage calulations. On the way to upstate NY, my top was off and just half doors on. I couldnt take any hills without downshifting and only got 168 miles to a fill-up. On the way back to Pa had everything on with just drivers window cracked and got 220 miles to a fillup along with no problems going uphill. Other things need to be considered like amount of hills and such, but my driving style was the same both ways and some traffic on the way back. But there was a huge differance.
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Old 07-28-2008, 01:42 PM   #25
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Actually it gets about 2-3 mpg more with the top, doors off and the windshield down. The windshield down varies by state laws as to whether you are required to have eye protection or not. Other than a few double takes from troopers here and the occasional wet bug in the kisser I've not had a problem, I just tried it one weekend out of curiosity. You will also need to take off the bars from the rear hoop to the windshield, they make this really annoying whistling sound and the vibrate a lot..
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Old 07-28-2008, 01:55 PM   #26
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Lol ^ how about a motorcycle helmet? It should be legal that way right?
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Old 07-28-2008, 03:41 PM   #27
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AeroDynamics = none found!

Don't waste your time worying about it, at best it is a few cents per tank difference, just drive it and enjoy it!
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Old 07-28-2008, 11:24 PM   #28
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It's funny that this topic was posted because after my new tires and the gas the way it is I have decided to do some test. So far after 3 weeks with soft top up no windows and doors off I am getting about 11.5 mpg. I am now testing the soft top up windows and doors on with the full door windows down. I think after a few weeks of that im gonna try doors/top on with the ac blowing. I know my mpg sucked in the first place and with the recent additions I lost about 3 mpg.

I don't know about how true the myths tested on mythbusters are but there is one damn thing for sure. Keri Byron makes it worth it for me. Also they did come to the conclusion that the airgate actually did the best.

Tripp I actually think Jerry did put you on ignore...hehe
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Old 07-29-2008, 12:15 AM   #29
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Tripp I actually think Jerry did put you on ignore...hehe
lol seems like it, he has repeated the same thing i said few times now. (not this thread)
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Old 07-29-2008, 12:54 AM   #30
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lol seems like it, he has repeated the same thing i said few times now. (not this thread)
haha

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