Gentlemen, I'm brand new to the forium and I have two Priuses and while going through all these statements I have read about fuel mileage, I have a few questions.
1.Is the fuel mileage based on a full tank?
2. Is the fuel mileage based on hypermiling for a mile or so, such as 80 MGP during that time and mileage?
I'm doing my darnest to keep my hwy mileage above 53 over a 40 mile round trip in my 05, my wife won't let me drive her 07, she says I will mess her seat, mirror and radio adjustments.
Last night I reset them all!
Ed

Welcome to the club! (BTW, we have most excellent lady experts too.)
No as long as the method gives reasonably accurate numbers. Click on my Prius signature block and you'll see that until recently, I was doing two fill-ups per week. This let me keep my commuting mileage separate from my weekend mileage and fairly quickly identify what works and doesn't work.
Using shorter intervals requires attention to detail to make sure the car is in the same state before each run. I've got a Graham miniscanner and know how to 'normalize' the car. It can be done but it takes attention to detail and you really need to make multiple runs to make sure the results are reproducible.

I find the biggest challenge is making sure the car is properly warmed up. As a general rule, I prefer to run at speeds above 42 miles per hour for at least 20 minutes.
If you warm-up the car before highway speeds and keep the cruising speed around 65 miles per hour, you should be in good shape. For good measure, take a peek at the FAQ in the Prius forum. For an 05 Prius, you might also want to have your alignment checked when you next rotate the tires.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

bwilson4web
Didn't mean to slight the ladies, I'll watch that in the future.
I thank you for the information, I'll try to keep it at or below 45 when I'm trying to increase my mileage.
I should add that my first mile is slightly up hill, then the next 2 miles are slightly down hill. I can coast for about 1 mile with no arrows showing., is that hypermiling?
also my AC and headlights are on.

Thanks again for the information.
Ed

Hi Ed,
You might want to consider getting a block heater and using it year round. The Japanese drivers, thanks to Ken@Japan, first told us about this and the technique appears to be fairly effective. You are pre-heating the block and shortening the warm-up.

The only other caution is to avoid transiting 42 miles per hour, a major boundary between the low speed, hybrid modes versus higher speed, engine always running. I try to stay in the 0-38 miles per hour and 45-65 range. Speeds closer to 42 miles per hour can lead to the worst of both worlds. <grins>

GOOD LUCK!
Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.