Go with what gives you a comfortable ride and a clear conscience. I run mine at 50/50 and ran my OEM at 44/42 for 3 years.
In warm temperatures I get about 54-57mpg to a tank at 42/40. Could I conceivably sniff 60mpg if I go a little higher or does the advantage in mileage decrease as you move to a higher PSI?
I agree with most of the posts here. Short commutes with hills are going to return low mpg. We normally get 48-52 mpg on every tank year round (SoCal weather) but on our current tank we're seeing 43mpg so far. Reason? Since filling up two days ago we've taken nothing but 3-6 mile trips, a couple of them up the 2 mile long hill that starts 2 miles from our house. Be happy with your 35mpg. I get 17mpg on the way up that hill (of course 99mpg all the way down). You've got to get past the first 5 minutes. Also I've never experienced the ideal conditions that allow for higher mileage on lower speed limit streets. My experience is the stop and go of stop signed corners, or traffic signal corners, reduces my mileage. I simply don't have any places where I can drive 30-45 miles per hour for more than 1/2 mile or so without hitting a forced stop. Freeways in SoCal are very common and if I stay in the slow lane and go about 60mph my mileage will always be over 50mpg per tank - as long as I can stay off the lower speed limit streets. A ScanGuage II might help a little. I'm always guessing at the optimum acceleration and have thought about buying one. Actually I think the smart move might be to buy the ScanGuage for my Honda Odyssey!!!
A lot of people have touched on the reasons you will see 'poor' fuel economy. With your short trip, the engine simply doesn't have enough time to get to it's operating temperature and stay there. Every engine in every car will behave the same - poor fuel economy until the engine is warmed up. As for the electric system starting the acceleration, it will under some conditions. One of which being that the engine is warmed up properly. The second is relatively low throttle demand. (meaning, if you don't stomp on the pedal, but give it just a little pressure) If you push the pedal too much, the engine comes on to provide torque. I'd say you're a victim of your commute. You simply won't get great fuel economy with that short of a hop. I was in the same boat a few years ago when I had a Honda Insight. I lived 2.1 miles from the office. The poor car could not get warmed up and could not charge the batteries well at all. Fuel economy suffered. I figured out that the Insight needed ~12 miles or more in a trip to do well. I would guess the Prius is close to the same. I'd also agree with the sentiment that a plug-in car would be awesome for you.
I am a fairly new owner & only drive 7 miles to work & hampered a bit by lots of hills, wind & short commute as my vehicle doesn't get up to full/efficient operating temperature. I'd try the air pressure in your tires, a block heater & grill blocker. I'd try adjusting the percentage of blockage for temperature change & run it 365 & adjust it as needed. ?? There is a variance in drivers & the vehicles themselves. Some cars of the same year, model, etc. simply perform better than others. You may not be getting the mileage you would like, but I suspect you'll be hard pressed to find another vehicle (std auto) that will do any better. Someone posted on here about forgetting the bad mileage & only remembering the "good" tanks/mileage. It can also work the other way. I would also be interested in what mileage you get out on the road on a 100 mile + trip. For me, the Prius at 30mpg is still a fine car. I'd be happy with that under the right circumstances.
This has been said before, but it's always worth repeating: A short commute with bad mileage beats a long commute with good mileage. Not driving is the best mpg you can get. Tom
I raised my tyre pressure from 42/40 to 52/50 and there was no improvement that I can measure. In fact I still haven't matched my best tank which I got at 42/40PSI in the tyres. My next tyre check I'm dropping the pressure to 44/42. Hard tyres are harder on the rest of the car, like shaking the MFD apart.
I'm more concerned about the expensive electronics, personally this old man likes a hard ride, and a car with firm suspension.
Regardless of whether there is any increase in MPGs, I don't want to go above the 42 to 44 range. First of all, the tires (OEM, that is) are rated at 44psi. Second, I tried going higher, and the ride became a bit more jolting than I cared for! At 42/40 or 44/42, I've been able to get 600 mile tanks on several occasions (60+ MPG). More would be better, I suppose, but the ride was just too hard when I tried it.
Me too... compared to my last car, the Prius is a creampuff. I'll eventually work on stiffening it up a bit.
um, if you are 2.5 miles away from work, i suggest biking. I wish i lived closer to my college so i can bike. You are very lucky.