While it may be fun to try to imagine what might be going on internally, none of us know enough about the internal programming to know HOW they are compensating (or not) for various variables. THAT is all pure speculation. The idea that the ECU would completely compensate out the changes cause by the spacer is speculation and in the end seems to be completely wrong.
As for babying, while my babying increased with the larger tires, I seriously doubt that was the explanation for the MPG drop, it was you know.. the larger tires, higher weight, less gear ratio and higher rolling resistance. A fairly well known phenomenon that my testing clearly backs up. Secondly, my levels of babying are the same before and after the block was installed SO that is ruled out as a variable. If anything, my MPG should go up even further now if I stop babying it maybe? In any case, that variable at this point would only positively affect the results, not negate them.
My samples are about as controlled as you can get without significant vehicle modifications and I went to some work to get them that way. My random deviations due to pump shutoff and weekend driving are smaller than the gains and losses when changing the tires and the using the spacer.
Finally, yeah frankly, (Speaking generally here, not specifically to you) if having to live with the type people who can take 100 years of research and thousands of scientists collecting data all converging onto one completely inescapable conclusion, pop their heads out of the sand long enough to yell "BULLSHIT". Combined with the people that instantly believe the most radically stupid things someone says without the tiniest bit of self reflection, or experimentation, or rational thought at all does make me frequently think that maybe this planet isn't for me
Let me try to explain it from a professional perspective. I have been making sense out of component and machine performance for 25 years. Sure, the machines and components I work with go much slower and are much bigger than a passenger vehicle but hey, math is math lol.
For you personally, you bought a component, installed it, documented data in the most non biased way possible for you and are now convinced this component works as advertised. That's fine and If I were personally evaluating it I would do the same thing because hey, what else can you do right?
In regards to your data and methodology: The longer you document performance the better your results will be. I think [MENTION=118321]Jetboy[/MENTION] and [MENTION=56924]mom[/MENTION]o have both mentioned it in previous posts. Also, using a simple average, while good enough to prove it to yourself, is probably not good enough to convince others. There are so many variables to contend with when talking about the efficiency of a vehicle. Momo asked earlier about some of them and you answered to the best of your ability. So how do you take variability out of the equation? Time and lots of data gathering. In addition to that you will need to use a trailing average of some time duration instead of using the raw data average in order to determine the actual efficiency change. Here is an example:
Every fill up I calculate the mpg by dividing miles driven by gallons used right? There are lots of variables even doing this simple task. One click, different stations, different temperatures, different blends, etc. I know you did the best you could to mitigate these variables but they exist no matter how careful you are unless you do them in a lab. In addition to that you have countless variables when driving you need to get rid of too. How do you do it? Again, time and data gathering. Let's say I filled up 10 times and got 19, 17, 18, 21, 17, 18, 20, 19, 18 and 21 mpg. The average is 18.8 mpg. Now you install different tires, eco block or something else. You do the same thing ten more times (19, 16, 21, 21, 20, 18, 17, 20, 21 and 20) and get 19.3 mpg from those ten data points. You compare the two and see you have improved a half point correct? Well, you have improved a half but why? Was it the mod or was it some other variable that caused the rise? Now let's look at it a different way. Let's add up five (in order) and divide by five to get a point average in time.
Your first point average would be 18.4. That is the first five (19, 17, 18, 21, 17) points added together and divided by five. Next you add up five more but start with the second data point. This would be 18.2 mpg. What you are doing is smoothing your mpg by using a trailing average function.What this does is take out variables. So now let me calculate it using a five period trailing average:
18.4, 18.2, 18.8, 19, 18.4, 19.2,..(one, two, skip a few lol)....and the last point is 19.2. So in this simple case, instead of increasing this hypothetical mpg by a half a gallon, by taking out many of the variables you actually increased it eight tenths!
My point is using slightly different math and taking a LOT of data points will give you a much truer picture of actual performance. I have actually volunteered to do this (even though [MENTION=121742]Quirt[/MENTION] should be doing it) just because I think the forum needs the good, real data. Quirt's a smart guy. He is selling these things based on testimonials instead of actual, real data. Much easier to do right Quirt?
If you send me your data I will start a plot and do the math. This way we can see what it really looks like with some of the variables gone. PM me for email address.
I wanted new tires!
