Trip from Newport RI to Stanford CT and back 280 mile trip yesterday at night in rain got me 40.1 mpg there and 41.3 back doing 60-65 and I try to get behind a bigger vehicle or a line of vehicles - if the line of vehicles is big enough they get the air moving your way and it greatly reduced drag. I was going 65mph and getting 55 mpg for a while behind a tractor trailer truck. I also noticed that my terminal speed going down the Newport Bridge was 53mph and it used to be 45mph . . . I still could not coast all the way to the exit ramp with the xB but I have with the Geo . . . I also noticed that a wet road yields better gas mileage than under heavy rain conditions . . . if you think about it a gallon of water hitting the car is about 8 lbs that you have to provide energy to to get it up to the speed that you are traveling and a gallon can be hitting the car in less than a minute if it is raining heavy.
First update after new HX wheels and Insight LRR tires. It was dry but cold this morning, 32F. It took awhile for the engine to heat up, maybe because I have the vent open on my grille block. I took the very latest route, the one that elimninates 4 stop lights. While I did make a few hypermiling mistakes, I had a pretty good trip to work at 66.23 MPG. Previous best was 63.68 at 45F and raining. There is definately some room left to get closer to 70 when the morning temps get back into the 50's. Tonight's drive will be sunny and in the 60's.
Today was not much warmer than yesterday, 39F vs 32F. But since I am still learning the nuances and limits of the new tires and route with fewer stoplignts, there is still room for improvement over the 66.23 MPG from yesterday. I started off well this morning, beating yesterdays results for the first six of eight milestones during the trip that I track trip FE. By the mid point of the trip which is also the lowest elevation, I was at 82.3 MPG vs 77.6. By the time I got to my next milestone at the top of the hill I was down to just a 1.6 MPG advantage which would extrapolate to a 67.8 MPG trip. But then the worst thing that could happen, happened. The light at the bottom of the hill turned red due to a car from a side street pulling up to the light. I make this light 95% of the time, but this time I had to hit the brakes hard from 50 MPH on a downhill and then start from a stop when the light turned green. A huge waste of momentum that left me with a 65.0MPG trip. The one light knocked me down by 2.8 MPG!
Looking at my route options again. A variable like missing that particular light will invalidate any testing that I plan to do.
What a beautiful day for a drive! 72F, sunny and 5-10MPH southerly wind. So I decided to take the top off. Damned the aerodynamics I say! Just for good measure I rolled the rear window down all the way.
Woot! 65.45 MPG! That is another best for the trip home by 2.5MPG and the first time that my return trip was higher than my drive to work. Today's round trip was 65.23 MPG.
Current tank, 240 miles, 63.47 MPG.
The tires seem to be breaking in nicely. I read something over at tire rack that says it takes several hundred miles (or was it 1000?) for tires to shed the oils that are used to release them from the mold. I havent had any more understeer problems and am slowly taking corners faster to find the limit. The tires are much quieter than the Kumhos and even though they are 12PSI higher, they absorb the bumps much better. Smoother, quieter, better MPG (guestimated at 2-3). I can live with that just fine. Maybe I will get another 1 or 2 MPG when they fully break in. I am happy with my investment and the look of smaller tires and the HX rims is really growing on me. Anyway after my MPG stabilizes i will swap tires again to see how much it effects FE. Should be interesting.
Anyway no more updates until next Tuesday for the del sol although I will be online. Im off to Myrtle beach with the family for spring break. We will have the prius but in deference to the family who just wants to get there ASAP, I will be driving blindingly fast, approaching 75MPH at times. Hoping for 48MPG in the fully loaded Prius under those conditions. And if they make me turn on the AC, it goes downhill from there.