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Unread 07-21-2013, 09:30 PM   #16
Newtons3
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Not necessarily. There's no reason a muffler of the same type with the same size tubing will flow more air with less restriction.

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Unread 07-21-2013, 09:33 PM   #17
Charley3
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Originally Posted by MoparMech View Post
It's a Jeep......if you want good mileage get a Dart.
I just got it from 16 to 22 mpg highway. So clearly it can be improved.
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Unread 07-22-2013, 04:40 AM   #18
Newtons3
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Absolutely. I went this path with one of my 95 2wds and regularly got 21-22, real world. I know it can be done but, at some point, the desire to run bigger tires, more lift, and make more power make mileage take a back seat. The two paths are opposing goals. That said, improvements are achieveable.
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Unread 07-22-2013, 07:50 AM   #19
Azzy
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You want 25+ Mpg?

Change your mill. http://www.mercedesdiesel4x4.com
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Unread 07-22-2013, 08:54 AM   #20
cbenez1
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While I read this I see a lot of these cam swap and aerodynamic suggestions and wonder, After spending the money and time to undergo them, How much have you saved ?
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Unread 07-22-2013, 09:47 AM   #21
mschi772
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Quote:
Originally Posted by cbenez1
While I read this I see a lot of these cam swap and aerodynamic suggestions and wonder, After spending the money and time to undergo them, How much have you saved ?
For some people it's not simply an economic equation. For me, there is value inherent to improving upon an existing design, solving a problem, reducing negative environmental impact, or simply achieving something uncommon/difficult. I do a lot of things not expecting them to save me money/pay for themselves.
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Unread 07-22-2013, 03:22 PM   #22
Kevin108
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How are you determining your mileage?
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Unread 07-22-2013, 03:40 PM   #23
Newtons3
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Well said mschi772.
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Unread 07-22-2013, 04:55 PM   #24
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Quote:
Originally Posted by mschi772 View Post
For some people it's not simply an economic equation. For me, there is value inherent to improving upon an existing design, solving a problem, reducing negative environmental impact, or simply achieving something uncommon/difficult. I do a lot of things not expecting them to save me money/pay for themselves.
I'm the same way, but in a different way. lol. If I could figure out how to get a powerstroke under the hood I would. I am sure I could get 25mpg out of it.
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Unread 07-22-2013, 06:52 PM   #25
Charley3
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Originally Posted by Newtons3 View Post
Instead of CAI you might look at hot air. This is the way the hypermilers get the computer to lean out the fuel mix even more.
My AFE "cold" air intake isn't a cold air intake. That's just AFE marketing hype.

It draws air from same place as stock air box, but is much free'er flowing.

So it's a high flow warm air intake.

My 205F thermostat helps keep things warm.
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Unread 07-22-2013, 06:53 PM   #26
Charley3
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Not necessarily. There's no reason a muffler of the same type with the same size tubing will flow more air with less restriction.
I intend to use larger tubing.
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Unread 07-22-2013, 06:58 PM   #27
Charley3
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How are you determining your mileage?
I fill up before and after a road trip. I'm only testing highway mileage.
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Unread 07-22-2013, 07:10 PM   #28
mschi772
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Not that it's throwing your MPG estimates wildly out of whack, but if you can fill-up at the same pump at the same time of day, your calculations will be more accurate. Pumps vary, orientation of the vehicle at a given pump can alter when "full" happens, and temperatures can affect the volume of fuel that actually gets delivered per gallon (cooler mornings means denser fuel which means more bang for your buck).
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2002-2009 1983 Chevy El Camino
2009-2011 1994 Cadillac Eldorado ETC
2011-Pres 1996 Jeep Cherokee Country
Wheels wanted to buy:
4 or 5 Turbines, old XJ 5-slot,
KJ 17x7.5 6-spoke, or KJ 16x7 5-spoke alloy

Paying ~$50 per wheel--Classified ad HERE
Have 4 (oxidized) Lace and 5 Eccos for potential trade
Biologist
Dog trainer
Mountain biker
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Jeep owner
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Unread 07-22-2013, 08:29 PM   #29
MountainMan864
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Take backseat out and all bumpers off too.
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Unread 07-22-2013, 08:50 PM   #30
Newtons3
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Quote:
Originally Posted by mschi772 View Post
Not that it's throwing your MPG estimates wildly out of whack, but if you can fill-up at the same pump at the same time of day, your calculations will be more accurate. Pumps vary, orientation of the vehicle at a given pump can alter when "full" happens, and temperatures can affect the volume of fuel that actually gets delivered per gallon (cooler mornings means denser fuel which means more bang for your buck).
I check fuel mileage religiously on every vehicle I drive. It's a bit of an OCD for me. That said I always hate to quote a single tank. I have never found that ambient temperature of the fuel when I fill up makes any noticeable, trackable difference. In our state, the pumps are tested and regulated and you can be assured of their accuracy. The tolerance between pumps is negligible. Unless I've made some change to one of my Jeeps, the biggest factors affecting my fuel economy are average speed, air temp, a/c duty cycle, and humidity. Methanol as an oxygenate factors in, but that's purely mathematical.
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