Edge isn't "pumping up the computer read out to make people happy". The truck's computer thinks it is using less fuel than it really is.
I don't know what model programmer you are referring to but lets take my Edge Juice for example.
My Juice plugs in between the truck computer and the injector harnesses (front 3 on one plug, and rear 3 on second plug). It also plugs in-line of the MAP sensor (reads and fools boost reading to truck computer), along with another that I'm drawing a blank on at the moment.
The Juice takes IN what the truck computer is telling the injectors to do, modifies injector duration, and then the Juice commands the injectors. So what the computer is telling the injectors to do and what they are actually doing is two different things. This is why the fuel economy meter of the truck reads significantly higher than your actual fuel economy. The higher the power level, the higher the difference in the two calculations. This is one of the ways you get more power, the truck tells the injectors XX-duration, the Juice then 'amplifies' XX, then injectors react at the amplified value.
I ran my Edge on stock (0), 1, 2, 3, 4 on the same road at the same speed (SLC to near Denver when I was working there last year) every other week for months. My hand-calc mileage never suffered from the changes in power levels (or went up), but my overhead reading would get wild high. On setting 1 (what I normally run), it usually reads 3.5-4mpg higher than actual. 0 reads 2-3 high, I've never removed the Juice to see if they get any closer. This was done on an empty truck, cruise set at 70mph, and only 1 stop in 465mi for fuel (stop mid way because it was the cheapest along my route), my hand calc was 19.7-21mpg, overhead was approx 20.8-24.6 on setting 1.
When towing (on level 1). My overhead still reads high, but the numbers are closer. Remember that the difference in the readings can be considered a percentage of error, and at 0mpg you are still getting 0mpg and the overhead knows that you haven't moved. So when you are getting lower fuel economy (due to towing heavy), the overhead will read closer to your actual economy... Mine were ~2mpg different at 12.5mpg while towing.
Hope this helps you understand what is going on with your rig a little bit.
Also, I'm running my stock sized tires at 80psi, and when I hit the highway I rarely stop till I need fuel. On an empty truck at 65-70mph, I can bet that I'm going to get at least 20mpg as long as I didn't have a headwind.
I don't know what model programmer you are referring to but lets take my Edge Juice for example.
My Juice plugs in between the truck computer and the injector harnesses (front 3 on one plug, and rear 3 on second plug). It also plugs in-line of the MAP sensor (reads and fools boost reading to truck computer), along with another that I'm drawing a blank on at the moment.
The Juice takes IN what the truck computer is telling the injectors to do, modifies injector duration, and then the Juice commands the injectors. So what the computer is telling the injectors to do and what they are actually doing is two different things. This is why the fuel economy meter of the truck reads significantly higher than your actual fuel economy. The higher the power level, the higher the difference in the two calculations. This is one of the ways you get more power, the truck tells the injectors XX-duration, the Juice then 'amplifies' XX, then injectors react at the amplified value.
I ran my Edge on stock (0), 1, 2, 3, 4 on the same road at the same speed (SLC to near Denver when I was working there last year) every other week for months. My hand-calc mileage never suffered from the changes in power levels (or went up), but my overhead reading would get wild high. On setting 1 (what I normally run), it usually reads 3.5-4mpg higher than actual. 0 reads 2-3 high, I've never removed the Juice to see if they get any closer. This was done on an empty truck, cruise set at 70mph, and only 1 stop in 465mi for fuel (stop mid way because it was the cheapest along my route), my hand calc was 19.7-21mpg, overhead was approx 20.8-24.6 on setting 1.
When towing (on level 1). My overhead still reads high, but the numbers are closer. Remember that the difference in the readings can be considered a percentage of error, and at 0mpg you are still getting 0mpg and the overhead knows that you haven't moved. So when you are getting lower fuel economy (due to towing heavy), the overhead will read closer to your actual economy... Mine were ~2mpg different at 12.5mpg while towing.
Hope this helps you understand what is going on with your rig a little bit.
Also, I'm running my stock sized tires at 80psi, and when I hit the highway I rarely stop till I need fuel. On an empty truck at 65-70mph, I can bet that I'm going to get at least 20mpg as long as I didn't have a headwind.
