2014 subaru forester 2.5 CVT MPG vs. RPM

[dkinsell]

So I just bought a new 2014 Subaru forester Touring 2.5 CVT. Because of the CVT I can't easily tell what has the best gear ratio at RPM and Speed. At 70 MPG I'm getting about 31 mpg and at 65 MPH I'm getting 34 MPG. Of course this is from the car's instrumentation which is not necessarily the most accurate. I know the CVT continuously adjusts to hit best efficiency.

But my question is this: Do I trust the CVT and its always at its most efficient point, or is there a distinct curve (or linear?) for MPG vs Speed.

So if it is always at its most efficient point, then I just drive slow. But if not, the I guess I log MPG vs Speed vs RPM just for my own reference. This is my first CVT (symmetrical) so I am not as confident as I was in the old Cavalier. There I could hit 5th gear and cruise at the lowest RPM to be most efficient.

Thoughts? Suggestions? Any other NEW foresters out there?

[user removed]

Aero drag is a square function of speed. At 60 MPH squared you have 3600 units of drag. At 70 MPH you have 4900 units of drag or 4900/3600 more drag for a 10 MPH increase in speed.

Aero drag is 70 % of your total of losses due to all factors combined at higher speeds.

With 36% higher aero drag at 70 its easy to see why mileage will suffer, although it is offset slightly by higher sustained load on the engine which improves efficiency slightly.

Not many here will own a brand new car but I have driven close to 80k miles in CVT equipped cars. Your mileage is very good considering the vehicle. A lot of people here will tell you you should have bought a manual, but there are many good reasons to choose an auto.

You would probably get 36-37 MPG if you slowed down to 60 MPH but that may not be possible without increasing the danger to yourself and other occupants. I did find neutral coasting (NEVER WITH ENGINE OFF) to see if it makes a significant difference, but I might not do that on a new car with a warranty, unless the manufacturer approved it an clearly stated it would not be an issue in case of a warranty situation.

regards
Mech