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Discussion Starter #1
It would seem to me if you increase the power output of an engine, you create a Higher HP:Weight ratio. Hence burn less fuel.

So in theory, If you increase the amount of air, (Cold Air Filter) increase the density (Larger Intercooler) and deliver better air to the intake it would give you more power and you'd use less fuel. And still get better performance.

Right or wrong?
 

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I think your on the right track. IMO, power adders to an extent will increase milage. But there are alot of variables that can come into play as well.



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Discussion Starter #4
BB
I don't know if you have experienced it or not. . . Being from the snow country and all.

I seem to get better highway mileage in the summer than the winter. That doesn't make sense!
 

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I think the reason for the bad winter milage is due to the fact of additives in the fuel to stop gelling.. I think that is what I've heard others saying on the forum. The additives seem to make fuel less effective. Summer fuel has more umph :peelout so to speak.
 

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Summer fuel burns hotter and more efficient to. Im not sure but iv heard that you cant make as much power on winter blend.
 
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Discussion Starter #9
haha I think the added whistle with power adders is my MPG drainer!:lol3:
I don't understand what you are saying.

Are you saying you get less mileage with the items I mentioned? Or the same???

I experienced a slite increase in my 04 just with a cold air.
 

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na I can get better if I keep My foot out of it! just joking around about hearing the Turbo Whistle.
 

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If I keep my Smarty on anywhere around 1 or 3 and I watch how im driving I can see and increase in Fuel mileage I havent figured it up manualy lately so not 100%, but the Lie-o-meter will say around 21mpg conservitavly. In real life prob about 17 or 18 need to figure it up though. Spelling sucks I know (need spell checker on reply boxes):thud:
 

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I'll give this my best shot to clairify:
Point #1, Does mods or higher HP give better mileage?: Typically, the way you increase HP, is by increasing efficiancy (like the CAI mentioned above) intakes, porting, turbo's etc. The increased efficiancy of the improved filter and plumbing design increases the engines ability to gobble air, and thus improves power. It also means that while cruising, your engine has to work less hard to get the air it needs to roll down the road. The energy that was formerly sucking in air, is now driving your rear axle. It's all physics, energy is not lost, only transfered.
What you have ALSO done, is increased the potential ammount of fuel and air your vehicle can consume at WOT (or any throttle possition really), so you can see a decrease in economy as well, if you don't keep your foot out of it.

#2, Better fuel economy in summer vs. winter. The "umph" QUAKE spoke of is measurable in BTU's. Summer fuel has more BTU's than winter. The higher volume percentage of addatives (anti-gel) in winter blend decreases the volume of actual Diesel in a gallon of fuel. Therefore, the BTU's (stored energy) in a given gallon of fuel goes down. So it takes more diesel to produce enough energy to drive you down a given ammount of road. While it is true that the winter air is more dense and has more oxygen per volume, the effect of this is smaller than that of the winter blend fuel, you simply don't see it. If we were driving turbo gas vehicles, you would see increased power in colder climate.

Hope all that is clear as mud...

Ryan
 

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Many power adders can increase mileage just by virtue of having more power off the line. I believe that this is where you make or break your mileage numbers. Everytime you stop your truck and then have to hit the accelerator from a stop you use a lot more fuel than just cruising. Try resetting the overhead while you are sitting still. Now give it a bunch of pedal and see what kind of numbers you see. I can tell you that my nice new truck tells me about 7mpg in that scenario. Now try going out on the highway and resetting it while you are cruising at 65mph. It may show you 30+mpg unless you are going uphill.
Anyways, yes, making more power can help your mileage as long as you don't "Enjoy" your extra power too much. Certain mods like intakes and exhaust may help mileage but usually the gain is minimal and not something you will notice and say "WOW!" Adding all the mods together may give you a nice noticeable gain in mileage....

This is just what I think.......
 

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I agree BB

I just invited you to a Mopar site on another thread. "It's here"
Good deal:thumbsup but the link doesn't work.

BB
I don't know if you have experienced it or not. . . Being from the snow country and all.

I seem to get better highway mileage in the summer than the winter. That doesn't make sense!
I lost on an average 3mpg with the winter blend.



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Great explination a2g! Thanks:thumbsup
 
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Discussion Starter #18
Any time. I dig physics :)
Heh

On paper the theory looks fine. But reality doesn't seem to make sense.

I did some extensive modifications to a gas job (Look at my Avitar) On paper, the physics rules were only partially taken in consideration. We were trying to determine what the actually MPG would be when we did everything. In that case, I hit the mark. 25 MPG Highway, 19 town. But I calculated 15 around town.. . Missed something!

Anyway, the same rules don't seem to apply the same to Diesel as they do to gas. I can fix the darned things, and understand the combustion process. But there doesn't seem to be as a dramatic increase when you do stuff like this on diesels.
 

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Sure, the reason is this: The most common way to make power with a diesel is add more fuel. Not so much increased efficiency. The rules still apply, and are not invalid. Just less noticeable (if at all), in a mildly modified truck. I didn't mean to imply that anyone who adds an exhaust or an intake is going to gain 3 MPG. In fact, I would bet you would not even notice in a tank by tank calculation. That doesn't mean that Diesel engines escape Physics. It is still fact that increased efficiency anywhere, will result in some amount of better MPG, MPG is simply a measurement of the sum total of your vehilces effiency. To say adding a free flowing exhaust won't help your trucks MPG is like saying 100 + .01 isn't more than 100. It is... just not noticeably more....
 

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Sure, the reason is this: The most common way to make power with a diesel is add more fuel. Not so much increased efficiency. The rules still apply, and are not invalid. Just less noticeable (if at all), in a mildly modified truck. I didn't mean to imply that anyone who adds an exhaust or an intake is going to gain 3 MPG. In fact, I would bet you would not even notice in a tank by tank calculation. That doesn't mean that Diesel engines escape Physics. It is still fact that increased efficiency anywhere, will result in some amount of better MPG, MPG is simply a measurement of the sum total of your vehilces effiency. To say adding a free flowing exhaust won't help your trucks MPG is like saying 100 + .01 isn't more than 100. It is... just not noticeably more....
Well said and Good Analogy!
 
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