Surprisingly, the 05-10 V6's don't get that much better fuel mileage than the 05-10 4.6L's; perhaps about 1-2 MPG better. But still, you should be seeing about 27-28 MPG at a steady cruise at 65 MPH, providing you're not driving like a retard and you're not running 4.10's.

First, understand that the on-board should only be used for info and NOT as a true indication of your actual fuel mileage. If you haven't already, confirm that the speedometer is correct by using a GPS. Once you rule out the electronics, go over the basics: fuel filter, TB, MAF, tire pressure, spark plugs, air filter etc. Exhaust restrictions (mainly clogged cats) are also mileage killers.

 

Yes, the car was very well maintained. It has a few repairs needed, but not much. Its awesome to drive that is for sure.

 

Ya, I did the calculations via the odometer and how much gas I pump in at the tank. 300 miles on the odometer / 14.5 gallons put in = 20.7 (this was mostly highway).

 

For hand-calcultaing to be accurate, you still need an accurate distance from the last fill-up to the next. If the speedometer is off, your odometer will be off, too, which is why it's imperative to verify the odometer is accurate before you go hog-wild on maintenace.

 

Aerodynamics have a lot to do with it.

 

Vette looks great! I've always liked the older Vette's, especially the Stingrays. Congrats!