In the midst of an exceptional tank

I don't post about my fuel economy much any more. I do well, in general, and don't usually feel a need to brag about each and every 'good' tank.

But even I'm a bit excited about the potential in my current tank. I've had good runs with my usual commute so far and hope to maintain things for another 200 miles.


BTW, this is the consumption screen for my trip home from work today....~15 miles.

 

<div class='quotetop'>QUOTE(JimboK @ May 6 2007, 05:28 PM) [snapback]436511[/snapback]</div>

Yea, that's the tough part...one day of several short trips, rainy weather and bad traffic and it's shot...and I've got at least another 200 miles to blow it!

 

<div class='quotetop'>QUOTE(GadgetMan2 @ May 6 2007, 06:06 PM) [snapback]436522[/snapback]</div>

Uh, I live in a hilly area too....But the final elevation at work and home are about the same. If you look at the photo this is a full tank mileage for 400 miles, not just one good commute. In fact, I often have better looking consumption graphs than this but had to drive during a busier part of the afternoon today.

Also, you can see my lifetime mileage in my signature. If you care to you can look up my tank to tank mpg at greenhybrid.com (same screen name) and see that my mpg has gotten progressively better over the 3 1/2 years I've had the car, with lots of sub-50 mpg tanks and a couple sub-40 mpg tanks in my first year, A few sub-50s my second year. An occasional the 3rd year, and none in the past year. I'm not trying to show any individual run or tank, I've had short commutes that averaged in the mid-80s and never post those...IMO they don't "count".

 

<div class='quotetop'>QUOTE(FireEngineer @ May 6 2007, 06:19 PM) [snapback]436525[/snapback]</div>

Maybe...we'll see, I'm on 3 pips and have been for over 50 miles...meaning I'll be at 2 very soon and those last two go away pretty quickly. I've never filled more than about 9.3 gallons so I'm a bit anxious about pushing too far. These early '04 tanks just don't seem to do as well as some of the later ones...at least mine doesn't.

 

I use an engine block heater and tend to get b/w 40-60mpg over the first 5 min. Closer to 25-30 when I can't use the EBH. Also, I maintain 1275 RPM and minimize battery use (ie I go really slow) for the first 30-60 seconds until the car completes Stage I. At that point I begin my routine of P&G with 'sweet spot' pulsing in the 1700-2300RPM range.

An excellent question. I DO exceed 42 MPH, but only downhill in a hyperstealth condition...ICE spins but no fuel flow.

I take the same route to and from work, but it is different than the one I used to use. None of the roads have a speed limit greater than 40mph and the first half (outgoing) is pretty rural. The second half is in the city.

I don't usually need to use EV mode except in the city stretch if I have stop and go traffic where I can exceed 35mph to get into stealth. I don't really pay much attention to the SOC other than to be sure I can stay in stealth at the end of longer glides. The car and technique take care of it.

I do keep up with regular traffic. I get passed once in a while by impatient folk, usually at rush hour and such, but I rarely go more than 2mph below the posted limit when there are other cars around. I do extend that low end a bit slower when I have the road to myself (not infrequent with my work schedule). I do not believe my driving should interfere with the regular flow of traffic, but I won't speed just b/c someone is on my butt either.

 

<div class='quotetop'>QUOTE(lazyleo @ May 7 2007, 01:18 AM) [snapback]436701[/snapback]</div>

Ray Moore posted a couple days ago and that's essentially what he does. Many of us hypermiler nerds feel that that is not the most efficient way to maintain that momentum. What we tend to do is feather the pedal so that there's no fuel flow and minimal battery flow to the wheels...that's what I mean when I say 'hyperstealth glide' in the questions I answered above.

The advantage, I think, is that as soon as you hit 41mph the ICE will shut off....it does not do that in Neutral. Also, the entire time you're in neutral there is a small amount of fuel being burned to keep the ICE spinning since it's disconnected from MG1...which is what keeps it spinning when in hyperstealth. Also, if you do need to brake you still get regenerative braking. In neutral you have only the friction brakes. Plus there are potential safety and legal considerations of using neutral this way.

But rest assured, the concept you're employing, in general, is the right one for maximizing FE at higher speed glide/slowing to stop conditions.

 

<div class='quotetop'>QUOTE(mparrish @ May 7 2007, 12:24 PM) [snapback]436933[/snapback]</div>

I can't cheat, it's an ethical thing for me. I do, sometimes, fill up with 2 pips on the display when I know I'm going on a longer drive. I do that both b/c gas tends to be cheaper where I live than anywhere else that I go and for the sake of convenience...so I don't have to fill up while away. And so I can use my 'favorite' gas pump.

But, in the abscenceof a good reason, I fill up just before or just after the last pip starts flashing. So yea, lots of potential pitfalls that could drop that mpg lower....lost 0.1mpg just this morning taking my kid's to school (short 5 miles each way with traffic).

 

<div class='quotetop'>QUOTE(dmckinstry @ May 7 2007, 06:42 PM) [snapback]437166[/snapback]</div>

We get cold spells from time to where it will be below zero (I think we had some -20 one day this year), lots of days in the teens and 20s with an average in the coldest months prob. b/w 35-40 degrees. Not terrible, but enough to get the battery and ICE temps down pretty quickly. I used the EBH religiously, park in a garage at home and really optimized that 'sweet spot' P&G.