[BHarvey]

After 3 tanks in the mid 35's I am thinking something is up with QT gas.
So, I found a station that has E-ZERO 90 octane ($3.76) so I rounded up a beaker and decided I would make the trip and test it BEFORE filling the car.

I got to the station and the pump was separate from the others. I had 50ml of distilled water in the sealed beaker and then put in 450ml of gas and shook it up real good. Then let it sit but it was almost instantaneous separation and the water was still at the 50ml line. The gas was crystal clear and smelled like gas instead of the putrid smelling stuff we get nowadays.

Anyway, I usually have one highway trip per tank consisting of a 100+ mile round trip that is around 25 miles of in town. My last 3 tanks being in the 35's had me pissed (messed up my average you know). The highest I had seen on the UG was 38 mpg in those last three tanks and that was at the start of the last tank in which I drove and good deal of highway miles.

My UG calibration reads .1 mpg lower than actual and has for some time and I am fine with that. The highest it has ever read for a "beginning of tank" trip
was 43.0 for a good 100+ mile combined trip in the dead of summer with ambient in the high 90's and the AIT at 140F.

Today after filling with the ever so sweet E-ZERO, I had about 10 miles of in town before hitting the highway. On the highway I drove like usual, 58-60 mph and only ever hitting 65 twice when fighting for position (the right lane).
Cruise up hills and coast down when the manifold pressure gets in the 3.9 range. No drafting. Was 70 and windy and I was getting blown around a little.
AIT was 110F or so.

When I got off the highway the UG showed 45.0 mpg and when I got home it showed 44.7 mpg. Seems like it shows less gph when on cruise up some familiar stretches.

I am going to try a couple tanks just to see what happens. I have heard some claim 10-40% less mileage with E10. Be interesting to see how my 11.3 CR handles it.

I'm like the man looking down Callahan's barrel, "I got's to know"!