13-14 mpg is killing me in the expy. 28 gallons using premium fuel.
so i picked up a 99 grand prix se sedan with the 3100 v6. seems to run good. just had a tune and battery. needs 4 tires and new headlight assemblies(wicked nasty). ordered the headlights off of ebay last night....of course they come from CA, so i wont see them until next week....maybe. still deciding on what tires to get. will get pics as soon as i can...i will have it at my dealership tomorrow night. supposedly supposed to get near 30 mpg highway and only an 18 gallon tank...and regular fuel!
That is a lot of MPG's for a V6. I would seriously look at the tire choice. Good tires can reduce your MPG's. I have seen 4-6 MPG's when going from Snows to regular summer tires.Testing
"This test reveals the possible advantage of using larger circumference tires/wheels to further reduce engine RPM for a given road speed. "
"Efficiency and engine RPM are not directly related, meaning that a 25% RPM reduction does NOT predict an efficiency improvement of "x%", nor does it predict any improvement at all - although RPM reduction will generally improve efficiency.
[Your] data proves this out. At first [you] get a 25% increase in RPM, but only a 15% MPG change (about 50% of the RPM change percentage). Later [you] test with a 48% RPM increase, but see a 60% reduction in MPG (150% of the RPM change percentage).
The efficiency of an internal combustion engine is largely influenced by operating RPM, BUT there is one "sweet spot", typically at or near "Peak Tq" that will return the best efficiency.
... I had a Bronco that got better mileage at 60 MPH than it ever did at 55 MPH, which certainly does not make sense based on the fact that the air drag at 60 is 112% of that at 55 mph, and the RPM is 10% higher as well."
Where is your sweet spot?