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Here we go again:
* The first two vehicles you compare are a Grand Marques and a Crown Vic. Both ordinary, and similar, low height sedans whose MPG performance matches reasonably. The faster you went, your MPG went down marginally.
RAC Yes and both behaved normally, a little faster and a little less MPG.
* Then you posted numbers for a Ford Explorer. An SUV. (This is like comparing apples to oranges). Because the drag coefficient is so much higher (inversely, because it so much less aerodynamic), the fuel efficiency is going to diminish at an exponentially higher rate at higher speeds than a sedan.
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RAC And again that MAY be True, but HOW is possible to lose 10MPG speeding up from 50MPH to 60MPH and THEN ONLY lose 2MPG going from 60 to 70MPH, and again ONLY lose 2 more MPG going to 80MPH?? Do the Math, exponentially higher rate at higher speeds so going at 80MPH SHOULD CAUSE A EVEN GREATER lost of MPG RIGHT??
RAC Also I drafted a big rig in I10 Northbound and got within ½ a car length and NO CHANGE
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You have also completely disregarded weight. The heavier an object is, the more energy it takes to propel it at a given speed.
RAC Your forgetting Nurton’s Third Law, a object as restt needs a force to move, and an object in motion will require force to stop it….a moving car or SUV at speed cruising needs very little force to MAINTAIN the speed…
My 03 Ford Explorer:
Power / Horsepower 239 HP @ 4750 rpm
Torque 282 ft-lb @ 4000 rpm
Curb Weight 4,381 lbs
2003 Crown Vic 3,942 lbs.
SUV is 439 pounds heavier the 03 Crown Vic about two full grown men.
The 2003 Ford Explorer has a drag coefficient of .41 Cd.
The 2003 Ford Crown Vic has a drag coefficient of .37
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This is not a programmed decrease in relative performance by Ford. If so, there would have been hundreds of class action lawsuits and federal investigations by now.
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RAC NO ONE questions it…you are dead sure I am wrong, you did not even fully read my points…everyone is 100% sure it is true, Trucks, SUVs and Vans CANNOT get good MPG BECAUSE of air resistance.
Part of why older trucks got bad gas mileage was because they were built to do what a truck was excepted to do, haul heavy loads, SO they were geared and carbed FOR that job, it just was not possible to build them both ways. Many trucks have a highway setting and a towing setting…
RAC Now with computer controlled system it could be done…by no one but a few people like me want better gas mileage and the answer is always buy a tinny little car. And very few have ever LOOKED for this…
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Your economic assumptions for MPG improvement cost savings are baseless. When talking about things like running 16.4 AFRs, water mist blended in with fuel injection, and what not.
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RAC GM did that 16:1 Air Fuel ratio trick in the PCMs of the 1985 to 91 Camaro’s with 305 and 305s running the TPI system. It was not allowed or used here BUT in Australia and New Zealand, it was. And I testing my 2000 Mercury was able to control its fuel ratios and gained a 5MPG by running 16.4.
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If you really want to improve your MPG measurably and at NO cost, put more air in your tires, drive defensively, obey the speed limit, and change your engine oil and air filter frequently.
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Done and Done, and you cannot see, read, of get any real change in MPG.
So I will keep trying to find an low cost way to correct this trick in two SUVs, which by the way one is 02 4.0 V6 and the other a 03 4.6 V8 and get one MPG difference between them.
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