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Discussion Starter · #1 ·
I have noticed that my 2006 XC90 gets reasonably good gasoline mileage up to a speed of 60-62 MPH. At that point, the mileage begins to disintegrate. Is there a new chip or a software program for the main computer on the XC90 that can/will improve gasoline mileage at the higher interstate highway speeds? Or, is the present reality one of Volvo/Ford's contributions to the wealth of the oil companies (much of travel is done at interstate highway speeds) <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/confused.gif" BORDER="0">
 

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Re: Computer Chip or program for XC90 (hjself)

No such animal. You can get a chip that will give you more power (IPD) but no better mileage<br>This is basic aero 101, large frontal mass moving through the air, same hp trying to move it. Needs more power to get said mass moving
 

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Re: Computer Chip or program for XC90 (hjself)

Well, you can drive slower, or lower your XC90.<p>As JRL said, its simple physics. You have a big, square shape that is not close to the ground so air goes over, and under it. This air slows the car down(drag) the car needs more power to move the air out of the way. <br>The effect isn't linear but exponential.
 

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Discussion Starter · #4 ·
Re: Computer Chip or program for XC90 (VolvoMax)

Max, I have a grasp of the aerodynamics involved. I understand the effects of air going over, under as well as around something as big as the XC90 "(Drag)". I greatly appreciate any constructive and/or educational responses that folks may choose to make. Other sorts seem to loose something in the presentation. I have been around the block a few times and I know and do not appreciate the feeling of being belittled or condescended to.<p>The reason I posed the questions that I did was because the mileage is great (22-23MPG) up to a speed of 62 MPH. At that point, the MPG drops "like a rock" to 17.5-18 MPG. The "mass" is already moving at a fairly good rate of speed. Your theory seems to have a "leak" in it somewhere. Could there be something else at play here?
 

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Re: Computer Chip or program for XC90 (hjself)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>hjself</b> »</i></TD></TR><TR><TD CLASS="quote">Max, I have a grasp of the aerodynamics involved. I understand the effects of air going over, under as well as around something as big as the XC90 "(Drag)". I greatly appreciate any constructive and/or educational responses that folks may choose to make. Other sorts seem to loose something in the presentation. I have been around the block a few times and I know and do not appreciate the feeling of being belittled or condescended to.<p>The reason I posed the questions that I did was because the mileage is great (22-23MPG) up to a speed of 62 MPH. At that point, the MPG drops "like a rock" to 17.5-18 MPG. The "mass" is already moving at a fairly good rate of speed. Your theory seems to have a "leak" in it somewhere. Could there be something else at play here?</TD></TR></TABLE><p>Are you talking about the instantaneous MPG shown on the trip computer? Really that doesn't give you a great sense of what the MPG is, it's just monitoring how much fuel is going through the injectors, basically. I never put stock in what that thing says only as an indicator of how you're doing. <p>I'd check your overall MPG by tracking mileage for each fill up for a while. See how that's doing for you. <p>Otherwise, no, there's no chip out there designed to increase MPG that I know of. Perhaps post in the XC90 Forum, there may be a known '06 problem.
 

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Re: Computer Chip or program for XC90 (hjself)

No leak at all.<p>Air simply builds up quicker the faster you go. This is true of cars, planes, whatever. <br>Accelerating at highway speeds will cause your mileage to drop.<br>Why do you think the EPA wanted everyone to drive 55?<br>Thats where cars are most efficent.<br>On SUV's the effect is even greater.<br>Heck, the EPA hwy mileage for the XC90 is 23 for a FWD and 22 for an AWD.<br>The EPA tests @ 55 mph.<br>So, it sounds like you are getting what the EPA said you should. There is nothing wrong with your car.<br>
 

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Discussion Starter · #7 ·
Re: Computer Chip or program for XC90 (needsdecaf)

Thanks for the thoughtful reply. As a matter of fact, I am using information from the Instantaneous MPG selection as well as the average MPG selection. And, thanks for the reminder about getting back to basics. I, for one, tend to overlook the tried and true on occasion. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0">
 

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Discussion Starter · #8 ·
Re: Computer Chip or program for XC90 (VolvoMax)

Max, thanks for the thoughtful reply. What you say makes sense. I guess I was looking for a "silver bullet" of some sort. O well, I guess there is no harm in dreaming and asking. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0">
 

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Re: Computer Chip or program for XC90 (hjself)

I would suspect the aerodynamics is a major part of this. The faster you go, the larger proportion of total power is devoted to overcome drag. Drag increases with the square of the speed. So for argument sake, let's pick 60 MPH as a base point since you are observing relatively good highway mileage. Going up to 65 MPH, you increase drag by 17%. Going up to 70 MPH, you increase drag by 36%. Going up to 75 MPH you increase drag by 56%. Going up to 80 MPH, you increase drag by 78%. All of these numbers are compared to 60 MPH.<p>As everybody has already pointed out, you have a large squarish front profile - i.e., poor aerodynamics resulting in large drag. Not a whole lot you can do to change the basic shape.
 

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Discussion Starter · #10 ·
Re: Computer Chip or program for XC90 (samulsoon_0503)

Thanks for taking the time to reply. I appreciate what you have shared. I also appreciate the way in which you have shared it. Thanks for the insight. What you say makes wonderful sense. <IMG NAME="icon" SRC="http://********************/smile/emthup.gif" BORDER="0">
 

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Re: Computer Chip or program for XC90 (hjself)

No prob <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0"> <p>There is a solution, sort of.<br>It would involve lowering the XC90 and installing a big front spoiler or air dam.<br>The XC90's upturned front end is a major source of lift.<br>How much mileage savings you would get is anybodys guess, but it would be better.
 
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