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After a few weeks of pushing incredibly hard, I decided to give the car a break for the rest of this tank and see what I can do within the limits of "normal operation." By "normal" I mean I'm doing basically everything I can for FE except frequent FAS. Results have been OK so far, all things considered. One daytime highway segment with the girlfriend yesterday was sub-par at 38.6mpg, but not too bad considering that the A/C was running for the second half of the 50mi trip. I also had a surprisingly relaxing drive home from eastern MA in the evening that netted something in the viscinity of 40.8mpg at cruising speeds of roughly 60mph. Finally, I made my 17mi commute this morning with only one FAS right at the very end (what's the point of burning gas while I coast into the parking lot and up to my space? ;) ). That was good for 41.0mpg. Again, not as good as the 45-ish mpg segments I was getting with all the engine killing but still quite acceptable for driving mostly between stop signs.

I'll be interested to see how the ScanGauge result compares to the hand calculation at the end of this one. Particularly, I wonder if its optimism on the last tank will reverse itself since I'm now taking advantage of the theoretical fuel cut-off while the car coasts down in gear.

Tonight I got to drive a friend's MDX, an Acura SUV thing if you
aren't sure what that is. She normally does 20-21 in it, but was
fairly open to my "mpghints" sheet and was willing to let me do
a little research to try and help the automatic-slushbox crowd.
I peaked at just shy of 27 on a fresh tank, the bulk of that
being interstate at about 62 mph but a little local stuff too.
It's got like three "D" shift ranges, presumably a lot of ratios
with the higher ones being overdrive-ish. Cruising at 62 mph
had the tach parked right around 1700, so that's not too bad. The
tranny definitely responds to "fake shift" pedal backoffs, and
bringing it on again slowly stays in the higher gears. From what
little I could tell; the thing is SO marshmallow-like it was
hard for the butt-dyno to really tell what was going on. But
I could watch the drops on the tach.
.
No particular tricks; no FAS, just smoothness. A couple of
NICE-on coasts here and there. The go-pedal, of course, has that
typical "fast bottom" annoying as hell jumpy response that they
all do, which seems to turn everyone into stupid drivers because
they *can't* feather without some serious control effort.
.
The brakes on the thing are abysmally squishy -- felt like I had
to go into it like a foot before anything started grabbing.
.
One weird thing was that it took *forever* to come back into gear
out of Neutral. You'd think an electronic-control trans would
be a little faster. I quickly learned to drop into D under no load,
wait like a half-second, and then add some go. I also noticed
that at lower speeds, taking my foot all the way off dropped RPM
down to like 1000 but reapplying would run it back up to
about 1400 before actually *doing* anything. Almost like it was
trying to "freewheel", but it was a tiny bit more drag than that.
Maybe that's just the slop of the torque converter? Which, I
noticed, went into lockup somewhere above 50 mph.
.
_H*

I recently did a "non-hypermiling" tank on my usual commute to see purely the effects of the aero mods on my car. I drove "normally" at "normal" speeds with the rest of the traffic and employed none of the tricks (ICE off coasting, etc.) that I normally use to improve mileage. Interstate speeds were 70 to 80mpg, rural road speeds were 55 to 65. I got 56MPG. In the past, on on long distance interstate trips in the mid 70's MPH, I would have gotten between 44 and 46MPG, so the aero mods are good for about 10MPG and remainder of my mileage improvement due to driving technique.

25% increase seems like a lot. Good job!

Hi Hobbit:

___You just needed a bit more time with her is all … The MDX is worth more then 27 just going down the highway at 62 mph. Add a FAS or two when coming to lights and she shoots up mightily …

http://www.cleanmpg.com/photos/data/505/33_1_MPG_Screen_Shot.jpg

___Good Luck

___Wayne

I just took trip in the civic. No hypermiling,, none what so ever. No wind, high 80's for temps. 95% hwy, 60 miles round trip with speeds up to 80 mph,,, rpms afew times over 6k and sg reported 46 mpg.

Its like when it wants to do great mpg,,, so be it. Or you can hypermile it and work yourself to death and get 44 mpg.

Darnist thing Ive ever seen.

Well, here's my take on FAS in a car not designed to do it as
part of its normal operation. I don't really like the idea of
killing *everything* besides the engine, rebooting a bunch of
ECUs, losing various functionality, etc. I'd be fine with a
generic injector-power cutoff, and I think that's a really easy
mod one could do to just about any engine since if you kill the
+ feed it's a ONE-WIRE mod. But then the problem [as Mike D. was
noting over in the "DC/DC converter" thread!] is that sometimes
the system gets confused as to why the engine stalled.
.
So I was pretty reluctant to go messing with this in my friend's
MDX ... heck, I tested the neutral-and-back-again thing *very*
gingerly at low speed, esp. after what Wayne was telling me about
MDX transmissions. [But hers is an '03, which supposedly fixed
those problems.] So in a car without the appropriate mod, I'll
probably limit myself to NICE-on coasts.
.
I'm so used to feather-footing my regen in the Prius that it felt
*horrible* using the brakes at all in the MDX, when I knew that
the kinetic of that monster was all just going up as heat. I don't
think I'll ever be able to drive a "normal" car again without
feeling that twinge. DWB aside, sometimes you've just got no
choice but having to *stop*...
.
_H*

How I feel about FAS in my vehicle keeps changing. On the one hand, I'm sure that even the most "extreme" hypermiling techniques are not even remotely as harmful as driving the car like a kid who just saw The Fast and the Furious and wants to beat on it like a F1 racer. On the other hand, the really ridiculously hard pushing I've gotten into has started to feel...wrong. Maybe it's just driver error, and I'm not doing things as smoothly as I ought to. But the constant on-off-on-off cycle, particularly on my low-speed stop-to-stop commute, can't possibly be doing good things. The clutch is a concern, as I really prefer to bump start over key starting. But there's also the steering system to consider, which is not designed to be operated without hydraulic pressure. As I've mentioned before, FAS requires that all steering force be transmitted to the rack through the column. Under normal operation, that force is dramatically reduced. I don't question that Honda built plenty of safety margin, so it's not like I fear that the thing is just going to fall apart. But what kind of wear and tear is that going to add over the course of 30, 40, 50k miles? Do I really want to find out?

So it's tough, especially considering that the technology now exists to push as hard as one wants without even the slightest reason for worry about the integrity of the car. The current generation of HCH and Prius just take it in stride and offer up even more for those who want it. Folks like Tarabell have proven that, and I'm sure that those cars won't have any more trouble than the same vehicle in another driver's hands. In fact, I think it's arguable
that hypermiling one of these hybrids puts even less strain on the mechanicals than the average American driver, owing to lower acceleration and braking demands, less suspension wear due to lower speeds, and less engine wear due to the preference for high gear ratios.

Now, it's not like I'm about to take the financial hit of dumping my 42.5K mile Accord for a new FE machine. (That would be quite opposite the message of CleanMPG, anyway. ;) ) But my personal level of effort may level off somewhere below where it is now for the sake of risk management. And I do think I'll be saving my pennies while keeping an eye on the hybrid market, maybe keeping this car for somewhat less than the decade that the sensible (maybe stingy?) part of me originally planned.

Uh, oh. I think I heard a groan come from the direction if Chicago :(.

i've been getting over 50 mpg segments when fasing every chance i get "either the engine is at load or its off" scenarios seem to work pretty well. For warm up though I wait till water temps reach past 50C before starting to do my first FAS. Pulse and FASglide every chance I get sometimes (even up hills!) anything to boost my average. I want to get a 50 mpg tank and I want it now!

The car just takes it, if hondas can be abused as we see today, I'm sure it can take "hypermiling" abuse.

Brick,

Your position is totaly understantable. There are lots of hypermileing tools available and no one (except maybe one person I can think of) does all of them. You know pretty much what the tools are. No one is going to fault you if you decide against using some of them.

I don't know if you guys have heard this, but in the ricer scene there are a bunch of people that have removed the power steering pumps and I think even the power brakes. I haven't heard of any major failures to the systems because of it. But it is something that is obviously a concern for some.

Just do your best. When you feel like pulling out all the stops you know how to do it.

As I stated earlier, somewhere, I have backed off on the FAS, mainly because it is hard work. I now use the 50/50 city/hwy route instead of the 75/25 route. My FE has suffered by about 2 MPG but the commute is 5-10 minutes shorter. I am happy with mid 70's. Pushing an 80+ tank might be fun once, but not sustainable enough to bring my average to the 80 mark. Sometimes you have to find the happy medium or you run the risk of hypermiler burnout. Of course Wayne is immune to that illness.:D

Sometimes you have to find the happy medium or you run the risk of hypermiler burnout. Of course Wayne is immune to that illness.:D

That's because Wayne is a machine. This whole 'back injury' thing? Yeah, not so much...upgrades. :D

How I feel about FAS in my vehicle keeps changing. On the one hand, I'm sure that even the most "extreme" hypermiling techniques are not even remotely as harmful as driving the car like a kid who just saw The Fast and the Furious and wants to beat on it like a F1 racer. On the other hand, the really ridiculously hard pushing I've gotten into has started to feel...wrong. Maybe it's just driver error, and I'm not doing things as smoothly as I ought to. But the constant on-off-on-off cycle, particularly on my low-speed stop-to-stop commute, can't possibly be doing good things. The clutch is a concern, as I really prefer to bump start over key starting. But there's also the steering system to consider, which is not designed to be operated without hydraulic pressure. As I've mentioned before, FAS requires that all steering force be transmitted to the rack through the column. Under normal operation, that force is dramatically reduced. I don't question that Honda built plenty of safety margin, so it's not like I fear that the thing is just going to fall apart. But what kind of wear and tear is that going to add over the course of 30, 40, 50k miles? Do I really want to find out?

So it's tough, especially considering that the technology now exists to push as hard as one wants without even the slightest reason for worry about the integrity of the car. The current generation of HCH and Prius just take it in stride and offer up even more for those who want it. Folks like Tarabell have proven that, and I'm sure that those cars won't have any more trouble than the same vehicle in another driver's hands. In fact, I think it's arguable
that hypermiling one of these hybrids puts even less strain on the mechanicals than the average American driver, owing to lower acceleration and braking demands, less suspension wear due to lower speeds, and less engine wear due to the preference for high gear ratios.

Now, it's not like I'm about to take the financial hit of dumping my 42.5K mile Accord for a new FE machine. (That would be quite opposite the message of CleanMPG, anyway. ;) ) But my personal level of effort may level off somewhere below where it is now for the sake of risk management. And I do think I'll be saving my pennies while keeping an eye on the hybrid market, maybe keeping this car for somewhat less than the decade that the sensible (maybe stingy?) part of me originally planned.

Uh, oh. I think I heard a groan come from the direction if Chicago :(.
Hi Tim,

Interesting Post you just did.

tiger

hey brick, just remember, to punch it once in awhile. After hypermiling for so long, your car feels pretty fast!!!

Not at the red light of course ;)

I think my 'happy medium' is going to result in some fairly respectable numbers. I just had a thoroughly enjoyable 106mi drive via the usual route to get home from RI. That's despite the 8mi, 1hr+ crawl along I-95 in Connecticut that was the result of nothing but heavy traffic and poor driving as far as I could tell. I left the ignition switch alone but used every other tool in the box, including plenty of NICE-ons to reduce consumption down the big hills and while closing the gap in DWB mode. That was 40.0mpg door to door, despite the traffic and net elevation gain.

It's very secondary, but I'm hoping to gain a couple of percent back on the highway with the aerodynamic enhancements that I have planned. My prototype lip spoiler is nearly complete (needs some Duplicolor to meet my minimum standards for taste ;) ). The many square feet of coroplast are waiting to be turned into underbody enhancement, too. I also plan to have some fun with tuft testing and vortex generators just for kicks. My expectations are fairly low for that kind of thing but it's fun to try. Literally any measurable FE gain would be well worth the effort!

hey brick, just remember, to punch it once in awhile. After hypermiling for so long, your car feels pretty fast!!!

Not at the red light of course ;)

It's funny, but I just can't bring myself to gun it except when absolutely necessary. It used to be a "cheap thrill" to get into the throttle on on-ramps, coming out of toll plazas, etc. but it really doesn't do anything for me now. Back then I had no real concept of what hard acceleration does to fuel economy, and figured my 26-29mpg tanks were just "bad luck" or something, and the 30-35mpg tanks were attributed to good traffic, moon phases, etc. Now I'm completely in the mind set of "Once you burn it, you can never un-burn it." Besides, the thrill of great FE is guiltless and almost free of concern for speeding tickets and the like...on level ground, at least ;) .

Had an OK trip this morning, btw. I took one FAS right at the end since I can't justify idling while I coast through the lot at 15mph and into my face-out parking space. That was 40.1mpg, and I know that I can do much better. I left late, was followed the entire way, and as such wasn't able to get crazy with the DWL.

It's funny, but I just can't bring myself to gun it except when absolutely necessary. It used to be a "cheap thrill" to get into the throttle on on-ramps, coming out of toll plazas, etc. but it really doesn't do anything for me now. Back then I had no real concept of what hard acceleration does to fuel economy, and figured my 26-29mpg tanks were just "bad luck" or something, and the 30-35mpg tanks were attributed to good traffic, moon phases, etc. Now I'm completely in the mind set of "Once you burn it, you can never un-burn it." Besides, the thrill of great FE is guiltless and almost free of concern for speeding tickets and the like...on level ground, at least ;) .

Had an OK trip this morning, btw. I took one FAS right at the end since I can't justify idling while I coast through the lot at 15mph and into my face-out parking space. That was 40.1mpg, and I know that I can do much better. I left late, was followed the entire way, and as such wasn't able to get crazy with the DWL.
Tim,

Hang in there. :)

tiger

sorry if you meant my thrill was to redline then i was wrong! I meant to say punching it as in (4000 rpms ;) just peak of the torque curve.

Most of my current tank (Which is coming to an end) have been "mild" hypermiling on the way to work. I REALLLLY take it easy the 1st 7 miles or so then jump onto the freeway and go 58-65MPH (The slowest I can safely muster on a moderately busy 70MPH limit) for about 20 miles before it turns to 65MPH limit, where I drop it down by about 10MPH.

I usually hypermile this segment on a parallel 45-55MPH highway but has gotten clogged with school traffic and been to lazy to investigate/find another route.

I've been clearing that segment about 8-10MPG under, compared to my parallel highway.

I try to make it up on the way home but isn't quite calculating that way. :(

-Steve

...I usually hypermile this segment on a parallel 45-55MPH highway but has gotten clogged with school traffic and been to lazy to investigate/find another route.
...

I will use access roads to the freeway when intersections can be avoided.

I like supermiling. :)

That seems to be where Im at. I know i can get 50 mpg tanks out of the Civic. Im sure theres even better in the car.

My goal has been to get thru the summer. Ive had to use the A/C and speed up. These efforts are netting my 47 mpg tanks. I can live with that! The 50 mpg tanks demand slower speeds, no A/C and basic P&G efforts with absolut throttle control. Takes alot more effort for alot less gain.

Im looking forward to the fall ,,, and yes winter months. Ive grown to really hate okie summers. With the reduction in heat I hope to get a few 50 mpg tanks in this fall and look forward to some testing with a WAI this winter.

Right now the civic is setting on a 50 mpg tank. Temps will go back into the lower 100's by thursday and friday. The A/C will come on and some will be lost. Im not going to worry about it. I hope in the next 3 to 6 weeks temps will start lowering and i can have some fun again. :)