Better Fuel Economy in Town vs HWY?

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Xjrguy

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If I keep the rear tires from going faster than the front, mileage is much better.

For anyone with a physics degree or experience;
Does the bed cover really help on these trucks with the short short bed? Does the airflow actually create a large enough low pressure area to matter?

I don't think it really matters in the long run.
 
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SVTRay

SVTRay

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I don't think it really matters in the long run.

For anyone with a physics degree or experience;
Does the bed cover really help on these trucks with the short short bed? Does the airflow actually create a large enough low pressure area to matter?

It''s been a while but I got to talking with some guys on TurboFord.org once and they mentioned some guys in the SOCA did some testing on this subject using Rangers. They tested the tail gate down and up as well as some covers. If I recall, they mentioned it didn't matter. Now me personally, I tested it out on my old Harley truck, made several out of town trips with and without a bed cover and found the cover to be helpful. My fuel economy on the hwy went from 16mpg to 17-19mpg.
 

bradyh20

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I have a degree in astronautical engineering, and the these are the things I think about a bed cover's effect on fuel econonmy:

1. It makes a difference
2. What kind of difference it makes will be different for every truck, every driver, every road, and each environment
3. If it was a significant difference, we'd already know
 

SuperRaptor

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I have came to this same conclusion in some vehicles and I think its because I drive at high speeds and no matter what terrain comes at me I expect the vehicle to maintain the speed I have it set it and therefore I will a lot of times get lower highway mileage than around town mileage. I just don't have the patience for 65 mph when I could be doing 80.
 

AuPanda

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Over the last 1,000 miles using 91 octane instead of the 87, I'vr gotten .2 mpg more. It's back to regular at the next fill-up.
 

Deinonychus

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My gas milage has actually gone down since I've installed the K&N drop-in. I took it out and replaced it with the stock paper filter and up went the mpg (about 1mpg). I figure I'll just use the K&N when i go off road since it's "cleanable."

If the stock filter gets better mileage than the K&N drop-in filter, then I think it's safe to say that the K&N drop-in filter yields less power than the stock filter.
There must be a great pressure drop (delta P) with the K&N drop-in filter than the stock filter.

A good question might be whether a conical filter (e.g., AirRaid, AFE) with greater cross-sectional area gets better mileage than the stock filter.
 

NoCaDiver

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RE: Kruat

Running a 5-Star 93-Performance tune on a 5.4L. Was getting 14 mpg in the city w/o beach driving on 87 octane. Now getting ~14.1 mpg with a couple of beach trips in there since the last reset. Haven't done any hard calculations as of yet.
 
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