Well, since its finally cooled down enough that I can tolerate driving without the A/C, I decided to do another highway fuel mileage test this time with 93 Octane E10 Premium.
For reference, earlier in the year before it got hotter than all hell, I did an 87 octane E0 highway fuel mileage test where I yielded just shy of 47 MPG.
For the 93 octane E10 test, I ran roughly the same route (although I went farther north this time to LaCrosse, WI Instead of going only as far as Lansing, Iowa..
What I noticed different this time with the 93 E10. The car handled the hills much better. I only had one where I had to drop to 4th to climb the hill, where before the car really struggled going up any real significant hills.
As far as the mileage numbers....
On the 93 octane E10 I ran 345 miles on 8.4 gallons. which yielded me 41.1 MPG...
I do need to mention however. I did switch wheels and tires since the last test. I ran the stock contipro's on 15" steel wheels for the 87 octane test, where this time for the 93 octane test, I ran 17" Painted and Machined Aluminum wheels. These tires are a bit wider than the 15's were. which probably reduced mileage a little just on that alone..
But Also I am expecting the ethanol blended in to the 93 also affected mileage...
Overall from the last test I saw about a 5.5 MPG drop with 93 E10 over 87 E0 and the wheel and tire swap.. These are still some decent numbers tho... I did find a place here that sells 91 E0.. and I will be testing with that at a later date, as soon as i finish off the tank i have now, and run at least 1 more 91 E0 tank to "flush" the system...
For the 87 test, I used 87 octane E0 purchased from Casey's General Stores..
For the 93 test, I used 93 octane E10 Purchased from Road Ranger.
All tests were done using normal driving techniques and running 55-60 MPH on the 2 lane highways, and 65-70MPH on the 4 lane highways with posted 65 MPH speed limits. On hills I would maintain at least 55 MPH climbing.. and whatever the car would coast at above 60 to 70 MPH on downhills.
87 test was at approx 5500-6000 miles on the odometer..
93 test was done at approx 10,200-10,550 on the odomter.
The 93 test was also done after having TSB 12-5-5 relating to poor throttle response on manual transmission cars applied.