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hypermiling RPM experiment

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Old 05-25-2008, 11:59 PM
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Originally Posted by Zman
I have gotten near 37mpg in my automatic.... going under 60 is best.
Two years ago I got 43 mpg with my manual. That was a 250-mile tank going 60 mph with no stopping, coming home from Exposed 06. Later I got a ScanGuage II which showed the car's indicated 60 mph was actually 57 mph.
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Old 05-26-2008, 06:46 AM
  #22  
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Originally Posted by vintage42
Originally Posted by Zman
I have gotten near 37mpg in my automatic.... going under 60 is best.
Two years ago I got 43 mpg with my manual. That was a 250-mile tank going 60 mph with no stopping, coming home from Exposed 06. Later I got a ScanGuage II which showed the car's indicated 60 mph was actually 57 mph.
I've been hypermiling hardcore, my tank should be pretty good.
I'm at 340 miles and i have another line left on the fuel gauge.
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Old 05-26-2008, 06:59 AM
  #23  
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Originally Posted by draxcaliber

also, be aware that shifting too early, too often and gassing it can lead to what they call "lugging" the transmission. which means that the low power from the engine, and load on the drivetrain can lead to the gears really straining to turn one another and actually push eachother apart and that is bad!

ACTUALLY it is called lugging the ENGINE



and you won't kill gears unless you have a TON of off throttle torque and hp



lugging an engine will however blow up clutches , ruin pressure plates and can spin rod bearings
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Old 05-26-2008, 01:09 PM
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Originally Posted by hotbox05
Originally Posted by draxcaliber
... be aware that shifting too early, too often and gassing it can lead to what they call "lugging" the transmission t is bad...
ACTUALLY it is called lugging the ENGINE...
When people speak of lugging the xB, I doubt that they know what lugging feels like, because it is hard to make the xB lug. I routinely shift the xB at 2000 rpm, and even if full throttle is applied at that rpm, the engine does not lug. This is because of its VVT. I have not felt the xB lug, and wonder if it is even possible.

Lugging occurs when the rpm drops to a point that the valve timing no longer works. The valves no longer open and close at the right time for the combustion process at such low rpms, so the combustion is not confined and released at the right times. The engine shudders, shakes the car, makes no power, and is about to stop running. The xB's ECU and VVT may make this situation impossible. The ECU might begin to cut off fuel to the engine as soon as the ECU determines that the VVT has reached the end of its lower range, before damaging lugging can occur.
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Old 05-27-2008, 01:38 AM
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it was something i read in click and clack about how shifting too soon, it puts alot of strain on the rotating components of the drivetrain, like the transmission gears and differentials. it said that it can put alot of strain on the teeth of the gears, and can even push them apart and crack and strain and so on.
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Old 05-27-2008, 12:38 PM
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Originally Posted by draxcaliber
... shifting too soon, it puts alot of strain on the rotating components of the drivetrain, like the transmission gears and differentials. it said that it can put alot of strain on the teeth of the gears, and can even push them apart and crack and strain and so on.
The total lack of power from shifting "too soon" puts no strain on the drive train.
For some drive train strain, try a full-throttle, high-rpm acceleration.
Or a good burnout.

You may be referring to what happens to the drive train during lugging. The roughness of the engine pulses can hammer the drive train. I have been unable to make the xB engine do this.

To experience lugging, find an older manual car or truck from the carburetor era so it won't have ECU or VVT. Back then, many people had a habit of shifting at low rpm or even skipping 2nd gear, and the engine lugged on the upshifts for a bit. Cab and delivery drivers especially did this, as it was considered economical driving.

Low rpm for lugging means in the hundreds, not thousands.
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Old 05-27-2008, 04:33 PM
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Originally Posted by draxcaliber
hahahahaaaa, no way in hell could the xB get 50+ mpg with a 6th gear! you are on some seriously strong stuff to speculate something like that.
Ohhh reeeeeallllyyy now.
Please allow me to retort...

The 5th gear in these cars is ridiculously low. 60 mph is around 3,000- 3,100 rpms. (just for reference sake, 70 mph in my wife's AWD CR-V is about 2,100 rpms!) Adding a higher ratio 5th, or better yet, a suitably over-driven 6th could accomplish amazing things in this car.
Now, on to your statement. My 5-speed 2006.5 xB has gotten a high of 43.86 mpg by driving very conservatively, using a light foot on the gas, shifting between 2,500 and 3,000 rpms, and attempting to keep the rpms below 3,000 whenever possible. I also covered 487 miles with that tank. My only mods were removal of the airbox snorkle and a K&N panel filter, and there was no butt-hugging on to semi-trucks, driving 45 mph on the freeway, or any other nutso practices in the name of higher mileage.
I know I could have done even better than that if I'd watched my habits every single moment on that tank, which I didn't. Admittedly, it takes a lot of discipline to pull off.
I know a couple of other guys on here have gotten close to 50 mpg, too, so my luck wasn't a complete fluke - so, back to the subject, why the heck is 50 mpg with a higher 6th gear only possible in your opinion as the result of a drug-induced stupor???
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Old 05-27-2008, 04:49 PM
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transmissions play a roll in vehicle MPG, more gears, more ratios, lower rpms at cruising. but if the xB could get over 50 mpg by adding a 6th gear, toyota has the gear box from the celica gt-s just sitting there, and i'm sure that with the rising fuel prices, toyota would have a freaking gold mine being able to sell xB's with epa ratings that high from adding a 6th gear. but they didn't, i'm sure they spent alot of time crunching the numbers and said this won't work because...

but can an xB maintain 60 mph at 2100 rpms? with wind resistance and only 108 bhp under the hood? how many hp does it make at 2100 rpms? either the engine can't maintain speed at those rpms, or it would put alot of strain on the engine to do that, leading to premature engine failure.

a cr-v has an engine about a liter bigger than the xB's, and while it is heavier and AWD, it probably has more power at 2100 rpms than the xB does at 3000 so it can cruise at that speed.
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Old 05-27-2008, 05:01 PM
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All true.
Unfortunately, all else aside, the "Celica" 6-speed is no doubt too expensive a piece for a low-roller like an xB, and bottom line is that at the end of the day, the car was never meant to be a high-mileage freeway cruiser. As I'm sure you're aware, really, it was supposed to be a "city car", as is so popular (and necessary!) in Japan. I've no doubt you're exactly right that Toyota did exactly all that number/feature crunching, and gave it that gearing that allowed it to feel "peppy" in that environment, but obviously kills it at open cruising speeds.
The point, however, was whether an xB could make 50 mpg with a 6th gear anyway, which I still firmly believe is possible!
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Old 05-27-2008, 05:38 PM
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Does anyone know if that 6-speed tranny(celica/ Corolla-Matrix xrs) bolt right up to our 1.5L engines ?
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Old 05-30-2008, 08:48 AM
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I'm getting 31-32mpg consistent now that it getting warm.
Curious thing is that when it was cooler this winter I was down around 28-29 with the same habits & gas. Even if I tried to drive nice I never saw above 30. Any thoughts on this?
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Old 05-30-2008, 11:03 AM
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Originally Posted by blueAZxb
I'm getting 31-32mpg consistent now that it getting warm.
Curious thing is that when it was cooler this winter I was down around 28-29 with the same habits & gas. Even if I tried to drive nice I never saw above 30. Any thoughts on this?
Winter gasoline formulations and colder weather conspire to destroy fuel efficiency. In my last car, I would consistently get 30mpg on the highway, and about 25 around town during the summer. Come winter, I was down to 28 highway, and 22 in town, without a change in my driving.
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Old 05-30-2008, 12:01 PM
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Originally Posted by WhoKilledTheJAMs
Originally Posted by blueAZxb
I'm getting 31-32mpg consistent now that it getting warm.
Curious thing is that when it was cooler this winter I was down around 28-29 with the same habits & gas. Even if I tried to drive nice I never saw above 30. Any thoughts on this?
Winter gasoline formulations and colder weather conspire to destroy fuel efficiency. In my last car, I would consistently get 30mpg on the highway, and about 25 around town during the summer. Come winter, I was down to 28 highway, and 22 in town, without a change in my driving.
Yeah, I've recorded my MPG year round and summer would be the best as high as 37 combined. Winter could be as low as 28 combined.

So for an acurate gauge of your combined MPG - you would have to observe your MPG for a whole year and then average it.
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Old 05-30-2008, 08:47 PM
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Originally Posted by typhoonorchid
Originally Posted by WhoKilledTheJAMs
Originally Posted by blueAZxb
I'm getting 31-32mpg consistent now that it getting warm.
Curious thing is that when it was cooler this winter I was down around 28-29 with the same habits & gas. Even if I tried to drive nice I never saw above 30. Any thoughts on this?
Winter gasoline formulations and colder weather conspire to destroy fuel efficiency. In my last car, I would consistently get 30mpg on the highway, and about 25 around town during the summer. Come winter, I was down to 28 highway, and 22 in town, without a change in my driving.
Yeah, I've recorded my MPG year round and summer would be the best as high as 37 combined. Winter could be as low as 28 combined.

So for an acurate gauge of your combined MPG - you would have to observe your MPG for a whole year and then average it.
Immediately after buying my xB, I started a spreadsheet. Once you get started, it's easy enough to keep your last gas receipt around long enough to punch in the numbers. I never was ambitious enough to do that with previous cars, but I know the xB is capable of impressive efficiency, so I'm making more of an effort to track my fuel use and driving habits. Besides, I like to make a game out of stretching my tanks of gas. Half the trick to being more efficient is to just be aware of it.
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Old 05-31-2008, 03:44 AM
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Originally Posted by Super-Stormtrooper07
Does anyone know if that 6-speed tranny(celica/ Corolla-Matrix xrs) bolt right up to our 1.5L engines ?
i think it does bolt up to the engine, but it doesn't fit in the bay, so you have to notch the frame of the car or something to get it to fit i believe.
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Old 06-17-2008, 07:53 PM
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I've been sayin since I got my box my only complaint would be it needs 1 more gear! A 6 speed would be phat!
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Old 06-17-2008, 07:58 PM
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Thought I'd post up some of my results, been using some hypermiling techniques and have seen a change!

Was averaging 31 to 32 mpg, and previous all time best of 35.1 mpg prior to changing habits and putting in a K&N filter. 3 tanks since, have all been 36 to 36.38!

Not Too Shabby!
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Old 06-18-2008, 06:52 AM
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Grimace,
Those are some phat numbers bro!!!!
Keep up the good job!
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Old 06-18-2008, 05:31 PM
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my 2c:

I too have kept a log of all gas purchases, dating back well before buying my 06 box. I've never been too light on the gas and preferred to enjoy the zippy nature that makes this such an enjoyable car to drive. You wouldn't exactly classify me as racer either though!

My lifetime mpg is 35.2, and the vast majority of that is a 22 mile commute in traffic, including 42 sets of lights! Yes, I've counted them... some days are just like that. Also, over 85% of the tanks have been between 33 and 37 mpg so it's very consistent year round (and I too see slightly better numbers in the summer despite AC).

For the last few weeks I've been playing (yes, I consider improving gas mileage a game) with keeping the revs lower and primarily being lighter on the gas pedal. Used to typically be 10 over the speed limit, now it's within 5. The last two tanks have been closer to 38. I'm aiming to get 40, just to know I can do it: it's been noted here before, but it takes patience and concentration to change a lifetime of driving habits, not to mention dealing with those behind who can't tolerate slower acceleration and speed limit.

I'm tempted to pick up a ScanGauge for that instant-gratification but I'm curious: how exactly does it determine mpg? What's it measuring for fuel consumption, is this fed from the engine management system? For those that have one, how does it compare to the pen-and-paper calculations based on fill-up volume and mileage (given the known 3% variance in odo reading, etc. etc.)?
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Old 06-18-2008, 11:56 PM
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Originally Posted by drbaillie
I'm tempted to pick up a ScanGauge for that instant-gratification but I'm curious: how exactly does it determine mpg? What's it measuring for fuel consumption, is this fed from the engine management system? For those that have one, how does it compare to the pen-and-paper calculations based on fill-up volume and mileage (given the known 3% variance in odo reading, etc. etc.)?
It plugs into the ODBII port, so yes, it's from the car's ECU. Someone else can probably answer your MPG questions or they've been posted before. You can save adjustments in the setup for tire or gearing changes so you could enter a correction. I recall someone posting that it actually has the correct odo reading and just displays a lower speed reading? I'm not concerned about a 3% variance.

Anyway, I say get one! I got mine just because the xB lacks gauges.
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