I have just finished my 3^rd tank full and I have modified my original results.  I made this modification because I chose the wrong comparison.  To be as accurate as possible and as fair as possible, I needed to consider 3 types of driving:

1.      local driving

2.      highway driving

3.      a combination of the two

When I made my first test comparison I used local driving when I should have sued combined.  So for my 1^st tank I drove 386 miles on 13.92 gallons and got 27.72 mpg which was a 2.14% increase.

For my 2^nd tank I drove 366 miles on 15.56 gallons and got 23.54 mpg which was an 8.04% decrease (I have no idea what happened there.  My wife actually did the driving for most of the 3 tank fills so I don’t know how she drove, except it was mostly back and forth to work.)

For my 3^rd tank I drove 433 miles on 16.54 gallons and got 26.18 mpg which was a 2.26% increase. 

I have started a test using my 1983 Ford truck and am on the 1^st tank.

I have purchased another company’s product and will begin testing it in the near future.

I will also let you know how my next couple of tank fills go.  I am looking for a tester who does a lot of highway driving to see how those results pan out.