Hi folks,

Although not a rigorous test, I track my MPG as a function of MPH and other environmental variables. Even before learning the ICE runs at any speed from 42 MPH and above, I'd observed a dip in MPG performance in the 40 and 45 MPH range. I just repeated the test using 42 MPH as the target and again got the worst MPG performance of any speed range.

I am returning to the following driving rules:

- 38 MPH is maximum low-speed range
- 52 MPH is minimum high-speed range (39-51 MPH is forbidden range)
- use ~1 mile warm-up route leaving from home and work
- use ~1 mile cool-down route arriving at home and work ('stealth mode')
- 'pulse and glide' 25-40 MPH traffic permitting

My commute routes range in distance from 10-13 miles with various combinations of speed limits. It typically takes 19-27 minutes depending upon route. My plan is to test using the shortest duration route and the driving rules.

Bob Wilson

 

for us canadians thats 61km/h ~~ the speed where I also drive in the city on with 2000 rpms in 4th gear. And 83 km/h for the minimum highway speed... which is also 2000 rpms @ 5th gear. Seems like 2000 rpms is still the sweet spot for my car according to the prius! Good data Bob!

edit: you can coast in deadband state with a classic right? And can you give more details about your warm up route? Do you accelerate slowly or do you try to spend as much time as possible during that 1 mile before starting to cruise at your normal minimal speeds?

 

Both our Prius and Echo have automatic transmissions so there is no 'gear' to select. My wife refuses to allow another manual transmission car. With the Prius, this is not a problem.

Below the MPG graph is a map and description of the routes and a comparision to our Echo. I had to use the Echo before the Prius and both use the same engine block and have simular performance characteristics except when fueling.

We use something called "Pulse and Glide" as described in this article:

"Hybrid Car Enthusiasts Achieve 110 MPG In A Prius
From Eric Powers,
. . .
The weekend of August 5th through the 7th, 2005, a team of hybrid car enthusiasts, took an unmodified Toyota Prius to a record breaking 1397 miles on a single 12.78 gallon tank of gas. That is a whopping 110 miles per gallon! This is an amazing accomplishment considering the EPA estimates for the hybrid is 60 city and 51 highway . . ."

The Prius I and Prius II can both use this technique.

Bob Wilson