74.4 MPG, love the Prius Fall

. .

Good commute home this evening, 62 MPG. In the Spring and Fall, I typically see 60+ MPG going home and mid 50s headed to work.

Summer is rough and I don't think it is just the intermittent use of air conditioning. As for winter, the challenge is the warm-up in the morning but closing the air inlet and the block heater helps. This may be the year I build the 'smart curb' to plug-in my Prius when I come home ... a Prius docking station.

Bob Wilson

...self-absorbed Facebook and FourSquare candidate.

Tell everyone how "regular" you are, as it happens, but that it doesn't smell.

. . . how "regular" you are . . .

Certainly consistent with Prius over personal content. Whereas if one simply counts Prius content versus personal angst, well it is easy to identify the whiners and cry-babies:

(Prius content words) / (Personal content words)

So I was over at Cars.com earlier this morning and they pretty well nailed down the Prius V:

They have three supporting articles that go into details:

What is interesting in this article is one of the first comments comes from a Chevy Cruz Eco advocate who completely misses the significantly larger interior volume of the Prius V.

Here they discuss the incremental fuel costs compared to their smaller Prius. There is no free lunch and a larger vehicle is not going to have the same mileage. The final article is:

Here they show the utility of the Prius V which is essentially the Prius station wagon. In particular, the ability to handle large, bullky loads for a family vacation.

So you see, it isn't hard, in fact, it is easy, to bring Prius content into a thread. But Prius content remains something beyond the abilities of a troll.

So take a break, step back, look the the totality of postings and who is bringing Prius content versus the Kabuki-like, sociopathic trolls. As I've pointed out before, trolls are entirely predictable . . . as if little invisible rods are attached to their 'buttons' and all it takes is the right 'stimulus' to make them move their little fingers and reveal how simple and useless they are. Absence of Prius content in a Prius forum is another tell.

Bob Wilson

Bob

This summer, I was able to achieve 70 mpg per tank twice (computed) which is 4 mpg than my best tank of 66 mpg last summer. While not

+74 mpg -- it's not too not bad for sustainable fuel efficiency considering that I'm using a 10% ethanol blended gas -- DC Air Pollution can be really bad so I don't want to complain about E10 too much ( code Orange and Red Days really suck) but its a FE handicap so I'm using it as an excuse for not doing as well as some of my betters. :-). .

these are my two top FE tanks this year ....

658 miles/9.39 gallons/70.1 mpg (8/1/11) 727 miles/10.25 gallons/70.9 mpg (9/29/11)

this was my best FE tank last year

340 miles/5.13 gallons/66.3 mpg (9/1/10)

I believe changes that help me achieve this improvement are:

1) increasing the tire pressure from 44 psi front/42 psi rear to 50 psi front/48 psi rear 2) the focused on using the Driving With Load (DWL) hypermiling technique has help FE along the mainly hilly terrain that I have to drive through. 3) using ScangaugeII Xgauge FwT, SoC, and GPH . to help avoiding having the ICE automatically run by pacing ICE operations to keep the battery charge up, the coolant temperatures up, and fuel burn rate low by avoiding the following conditions

SoC < 48%, FwT < 140F, GPH > 1.20,

This September - I've started grill blocking early in hopes of keeping my MPG slightly higher than last Fall. My strategy-experiment is to block the lower grill (ICE radiator) when the temperature drops lower than 65F. and block the upper grill ( HV inverter radiator) when the temperature drops below 75F. This is slightly more aggressive than Ken of Japan has advised so I am monitoring the coolant temperatures via the ScangaugeII FwT and will remove the grill blocking if the coolant goes to 200F. The hypothesis behind this experiment is that the ICE delivers better FE when it runs between

180F to 200F and since all my commutes/trips are less than 75 minutes and mainly under 45 minutes - the grill blocking helps the ICE achieve its optimum temperature range faster. Sofar, this tactic appears to be delivering higher instantaneous MPGs than last year at the same time.

I plan to drop my tire pressure back to 42 psi front and 40 psi rear for better traction on wet road sometime after November 1st (when the DC area gets more precipation and the daytime high to drop below 55F) and I'll either keep it there or lower the tire pressure further during the entire winter. I won\t consider upping the tire pressure back up until late spring ( upper daytime temperatures will have reach atleast 55 F with one or no rain days per week).

I've heard some fellow has insulated the 2010 Coolant Reservoir and put weather stripping around the hood to keep the car warmer in the colder temps - not sure if that's the way to go though...

I believe changes that help me achieve this improvement are:

1) increasing the tire pressure from 44 psi front/42 psi rear to 50 psi front/48 psi rear 2) the focused on using the Driving With Load (DWL) hypermiling technique.......

Last week I drove 60 miles and back. Weather service said the wind was 35 mph gusting to 45 mph. Perfect tailwind going, perfect headwind returning. Speed limit was 55, I had my cruise locked on 57 both ways. Going, I would have flat-lined at roughly 78 mph were it not for a couple of 100 mpg minutes as I passed through two towns. On the way back, I would have flat-lined at 48 mpg where it not for a couple of 55 mpg bumps when going through those small towns.

Given a constant speed, nothing effects mileage more than wind. The Prius design is such that the positive impact of a tailwind is much greater than the negative impact of a headwind of the same velocity. Because there is almost always some wind, it becomes impossible to accurately measure the subtle effect of a change in tire pressure but knowing one's wind-speed can dramatically improve performance when hypermiling.

Excellent news.

On Oct 10, 3:39 pm, Neo wrote: . . .

I think we all have to deal with 10% ethanol. I did a difference test with a local station that claims to sell pure gas . . . no difference.

. . .

My Sumitomos are at 52 psi, their maximum sidewall.

Regardless the branding, operating in peak engine efficiency region is the way to go.

I'm using:

coolant temperature engine RPM gallons per hour

I haven't found a need for anything else although I may use the OPEN/ CLOSED loop control to see how well it maps to the catalytic converter warm-up.

. . .

Good plan. I did a test last winter with a 100% block to measure highway speed effects and there was measurable improvement in hight speed drag with no risk to ICE coolant temperature.

You might want to test high and lower pressure effects in a parking lot. In particular when snow arrives. So far, I'm finding hard tires work all the time in North Alabama and I tested them in a parking lot. The harder tires seem to push the stuff away.

That is why we experiment, to find out.

Bob Wilson