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I just read this on an Instructables article...

"The best way to accelerate is by keeping your engine at peak torque. This means, accelerating too slow (as you may have been told to do) and accelerating too fast (bringing your rpms up high) are inefficient and will reduce your fuel economy numbers.

Ideally, peak torque at 50-75% throttle."

See the article here:

http://www.instructables.com/id/SD21HRXF5HVHRZ2/

Question: Is that valid information? If so...I'm accelerating WAY too slow!

Yes, provided you're also using low rpm at the same time. Read this article: http://www.autospeed.com/cms/A_110216/article.html

However, there is a time and a place for low, slow acceleration. I generally do slow, gentle accel from a stop, but at higher speeds I use the 75% throttle setting in a Pulse & Glide routine.

I had been wondering what the correct rate of acceleration was. I imagine too slow, then you waste gas because it takes longer to get to the glide, but too quick and you burn fuel... but what do I know LOL

... I generally do slow, gentle accel from a stop, but at higher speeds I use the 75% throttle setting in a Pulse & Glide routine.

I have been doing the same.
Seems from that article and others that putting you rpms in the cars power band would yield the best possible mpg on acceleration.
Example: my car has a peak at 2400 rpms so it seems to me I should release the clutch at around 1500 rpm (idle is 1100) and shift up at ~2200 using 25 to 50% throttle as I go through the gears.

That is my hypothesis, anyone want to shoot holes in it before I test it? ;)

I've been testing this lately. It's pretty clear, through my informal testing, that light throttle is the best option for accelerating from a stop. Light, light, light throttle, and low rpm - below 2,000 in my case.

Then when I'm up to speed, I switch over to heavy-throttle P&G.

I manage a 32mpg tank with the fill up today.

I'm going to try a heavier foot on the P&G this tank!

Hi All:

___For a std. Steady state cruise up to speed, just bring it up slow. For a P&G regiment, you all know the drill by now ;) All the gear heads born in the last 70 years have been trying to analyze this out on paper and on the boards all the while half the membership here has figured it out within months by just doing it with results so far beyond what the numbers and charts were/are supposed to allow. Don’t be jumping on the accelerator pedal with high R’s and max loads unless you want poor FE results. You can believe the books and charts and the millions who follow the BS or you can follow the real world results and take the excess and put it into the bank instead.

___Don’t worry, once you are instrumented, running with the proper setup, your tool box is filled and you know what tool to use at a given time, you have no choice but to put out numbers so far beyond your current expectations you will never look back :)

___Good Luck

___Wayne

You (The americans) always seem to assume an automatic :)

I try to accelerate at low rpm and with my SG showing 75% or so LOAD. This usually means 1100-2000 rpm and 4-th or 5-th gear. Consumption will then be around 15 MPG or less during the acceleration.

But I am starting to think there is a sweet-spot as to not doing this when your target speed is low. The MPG at NICE-on will be quite poor at low speed, so you gain little when you start gliding after the acceleration is finished...

But I am starting to think there is a sweet-spot as to not doing this when your target speed is low. The MPG at NICE-on will be quite poor at low speed, so you gain little when you start gliding after the acceleration is finished...

Only if you don't use FAS. ;)

I've been testing this lately and Wayne is exactly right. From a stop, bring it up slowly and lightly. At speed, in a P&G routine, that's where you use the heavy throttle. 2 different applications, 2 different answers.

Wild.

I'm now 70 miles in to a fresh tank..I was accelerating painfully slowly this morning, shifting at 2k rpm. I need my Scangauge!

How much throttle do you actually use to accel at highway speed? 1/2 more less...?

tomw: I use around half throttle at highway speeds (haven't checked what the TPS is as I just got my SG) but the load is surprisingly high, ~50 TPS = ~75-80% LOD (I'll have to verify this). See if you can find BSFC charts for your car, I know that for my TDI high load around 85-100% is preferable, but I tend to stay away from WOT. In general, (with a gas manual) you can try 75% throttle.

Kirk

Heres your test (assuming you have a ScanGauge).


Pick a landmark a mile or two up a deserted stretch of road.
Pick a target "cruising speed" say 45 mph.
Come to a complete stop a some "start point" and turn the car off so you have a consistent "start"
Go to your SG and reset "current"
Start your car and test your accel.
Test "low", "med", "high" accel curves up to your cruising speed then hold till you pass your marker
Check to see which curve consistently gives you the best results.


11011011

Hey Dan, as I read your test procedure it occurs to me that the ScanGauge must read out FE in hundredths of a MPG (two decimal places). True?
If that's true, I may end up having to get one after all, as my built-in only reads to the nearest tenth of a mpg, thereby probably necessitating a more prolonged test than you outline.
At any rate, I'll surely test this, as this question of how best to get up through the gears to cruising speed has been nagging at me for some time now.
thanks
-jon

Hey Dan, as I read your test procedure it occurs to me that the ScanGauge must read out FE in hundredths of a MPG (two decimal places). True?
No... It reads MPG XX.X but it reads gallons burned X.XX . So if you plot out a set 2 mile course, you can see your gallons burned over the two miles. Lowest gallons burned == Highest MPG.

11011011

Aha! My built-in doesn't show consumption. THAT's why I may need a scangauge.
Breaks my heart that I might need a new toy... :rolleyes: ;)

I also will have to agree with Wayne on the slow acceleration being best. With my current tank running at 86.0 on the Scanguage and 87.7 on the MFD in the Prius after 728.5 miles with 3 of 10 pips on the gas guage, I would say slow is best.:p

I guess I'm stumbling in the dark without a scangauge, to some extent, but the problem I see on my mid (mfd as you say) is that it shows FE in the teens when I'm going up through the gears, whether quickly or slowly. So it seemed to me that the quicker I can get up to cruising speed (not racing, mind, but within reason) and get my momentum up, the more time and distance I'll spend at higher FE. With my terrain momentum is important.

I guess I'm stumbling in the dark without a scangauge, to some extent, but the problem I see on my mid (mfd as you say) is that it shows FE in the teens when I'm going up through the gears, whether quickly or slowly. So it seemed to me that the quicker I can get up to cruising speed (not racing, mind, but within reason) and get my momentum up, the more time and distance I'll spend at higher FE. With my terrain momentum is important.Assuming a linear curve that kinda makes sense but it's not linear. Looks more like a stock chart. Think differential equations or something. Point is, it's kinda hard to calculate out on paper and even harder to hold to your calculations in the field.

But... Since I have excel open... lets run numbers. Think in averages on 0.1 miles.

Look at each tenth of a mile in the track from 0.0 to 1.0. Lets take average MPG over the tenth of a mile taking a new reading at each tenth

FAST ACCELERATION CALC
Mi|mpg|gals burned
0.1|5.0|0.020
0.2|7.0|0.014
0.3|9.0|0.011
0.4|30.0|0.003
0.5|30.0|0.003
0.6|30.0|0.003
0.7|30.0|0.003
0.8|30.0|0.003
0.9|30.0|0.003
1.0|30.0|0.003
---------|---------|---------
1.0|14.5|0.069

SLOW ACCELERATION CALC
Mi|mpg|gals burned
0.2|10.0|0.010
0.3|15.0|0.007
0.4|17.0|0.006
0.5|20.0|0.005
0.6|22.0|0.005
0.7|25.0|0.004
0.8|27.0|0.004
0.9|30.0|0.003
1.0|30.0|0.003
---------|---------|---------
1.0|15.0|0.066

As you can see, excel tells me that slow acceleration works better than getting up to high MPG quickly. The math is called weighted average and means that the bad MPG segments weigh heavier than the good ones. This is apparent when you notice the fast acceleration burns more than half of the gas in the first quarter mile. It's also why 4 miles at 10 mpg and 4 miles at 30 mpg does not equal 8 miles at 20 mpg, but instead 8 miles at 15 mpg.

11011011

But... Since I have excel open... lets run numbers. Think in averages on 0.1 miles.

Dan, are these actual numbers? Do you have access to the BSFC chart for the car these tests were performed on?

As you can see, excel tells me that slow acceleration works better than getting up to high MPG quickly. The math is called weighted average and means that the bad MPG segments weigh heavier than the good ones. This is apparent when you notice the fast acceleration burns more than half of the gas in the first quarter mile. It's also why 4 miles at 10 mpg and 4 miles at 30 mpg does not equal 8 miles at 20 mpg, but instead 8 miles at 15 mpg.

That's why L/100km is better. ;)

Kirk

Dan, are these actual numbers? Do you have access to the BSFC chart for the car these tests were performed on?Heck no, don't think it would matter even if I did. BSFC maps are good for forming theories, not proving them. For proof you need to put the tests to the field. I just made up an anecdotal example to show that spending 6 tenths of a mile at 30mpg may be less efficient than spending 2 tenths of a mile at 30 mpg. All depends on how you get there.

And yes... l/100km or oz/mi both can be averaged in a more common sense manner.

11011011

One of the reasons that you should not look too myopically at BSFC maps (or horsepower maps if you are drag racing) is the fact that the engine has to accelerate itself along with the car. The torque available to accelerate your car is the engine's steady rpm torque minus the torque required to accelerate the engine's flywheel and other rotary mass. The lower the gear you are in, the bigger the percentage of power consumed by accelerating the engine's own flywheel.
For this reason, I shift into second about as soon as the car is rolling fast enough to not lug in that gear before really starting to accelerate and shift early out of second also. In the higher gears, you can accelerate at the engine's peak BSFC load point.

If theory doesn't match real world results, then something wasn't taken into consideration.

Thanks BLE, well put.

Kirk

Can someone explain to me why it is preferable to accelerate slowly from a stop, but accelerate with moderate load for P&G? I've been trying to wrap my brain around that one recently...

-soD

Me too.
I think it is one of those times you just need to try it and see if you get results. It does seem to help me. But until I get my mpg stabilized I will not know for sure.

P&G is special in that you want to extend your coast as much as possible. The most efficient use of the engine is needed for the max speed -- this does not always correspond to the least use of fuel, though.

I know it is counterintuitive but the SG bears it out.

I understand that we're seeing the results from SG readouts, I just want to understand why!

It's pretty obvious that, to cut down on pumping losses, you want the throttle open at least a moderate amount. Of course, that will usually make you accelerate, taking you to higher RPMs than your most efficient range.

What I'm trying to reconcile is this:
Getting up to speed is getting up to speed. If you're doing a P&G from 35-45, or if you're simply driving from a stop up to 45 MPH, you are still trading fuel for velocity. If you use less total fuel getting up to 45 MPH slowly, then why don't we pulse slowly? Conversely, if running at moderate load on the pulse gains us velocity more efficiently, why don't we do that from a stop?

I understand that real world results are telling us that light acceleration is good when accelerating to a speed, and moderate acceleration when P&G. But I can't wrap my brain around what makes them different enough for our real-world results to show up.

Thinking about it more, it seems to be the difference between "max efficiency" and "minimum fuel usage" that I am having a hard time with.

-soD

I agree with soD, whether finishing a coast at 35, or accelerating from a stop to 35, shouldn't the acceleration portion from 35-45 be the same whether you got the 35 mph from a coast or from acceleration?

Maybe the SG results are because light acceleration is better when coming up through the lower gears.

Kirk

I understand that we're seeing the results from SG readouts, I just want to understand why!

It's pretty obvious that, to cut down on pumping losses, you want the throttle open at least a moderate amount. Of course, that will usually make you accelerate, taking you to higher RPMs than your most efficient range.

What I'm trying to reconcile is this:
Getting up to speed is getting up to speed. If you're doing a P&G from 35-45, or if you're simply driving from a stop up to 45 MPH, you are still trading fuel for velocity. If you use less total fuel getting up to 45 MPH slowly, then why don't we pulse slowly? Conversely, if running at moderate load on the pulse gains us velocity more efficiently, why don't we do that from a stop?

I understand that real world results are telling us that light acceleration is good when accelerating to a speed, and moderate acceleration when P&G. But I can't wrap my brain around what makes them different enough for our real-world results to show up.

Thinking about it more, it seems to be the difference between "max efficiency" and "minimum fuel usage" that I am having a hard time with.

-soD

I would also like to know this...

I understand that we're seeing the results from SG readouts, I just want to understand why!

It's pretty obvious that, to cut down on pumping losses, you want the throttle open at least a moderate amount. Of course, that will usually make you accelerate, taking you to higher RPMs than your most efficient range.

What I'm trying to reconcile is this:
Getting up to speed is getting up to speed. If you're doing a P&G from 35-45, or if you're simply driving from a stop up to 45 MPH, you are still trading fuel for velocity. If you use less total fuel getting up to 45 MPH slowly, then why don't we pulse slowly? Conversely, if running at moderate load on the pulse gains us velocity more efficiently, why don't we do that from a stop?

I understand that real world results are telling us that light acceleration is good when accelerating to a speed, and moderate acceleration when P&G. But I can't wrap my brain around what makes them different enough for our real-world results to show up.

Thinking about it more, it seems to be the difference between "max efficiency" and "minimum fuel usage" that I am having a hard time with.

-soD

Let's take a hypothetical car that has a 12 inch diameter flywheel on the engine with a mass of 30 lbs and lets assume that this flywheel is a uniform disk.
Let's assume that the car has a mass of 3000 lbs and the first gear ratio is such that the car is traveling 30 mph when the engine is turning 6000 rpm.

Here's the results of the number crunching:

At 6000 rpm, (100 revolutions per second) the flywheel has 22,988 ft-lb of kinetic energy.

The entire car has 90,186 ft-lb of kinetic energy.

The total energy (car + flywheel) is 113,174.

About 20% of the engine's power was consumed in accelerating its own flywheel.

What happens to the energy stored in the flywheel? Most of it gets dissipated by engine braking as we shift to the next gear. If we shift like race cars, most of the energy is used up in friction as the clutch slips to match the engine speed to the next gear.

Perhaps this may be a factor in this apparent paradox.

Let's take a hypothetical car that has a 12 inch diameter flywheel on the engine with a mass of 30 lbs and lets assume that this flywheel is a uniform disk.
Let's assume that the car has a mass of 3000 lbs and the first gear ratio is such that the car is traveling 30 mph when the engine is turning 6000 rpm.

Here's the results of the number crunching:

At 6000 rpm, (100 revolutions per second) the flywheel has 22,988 ft-lb of kinetic energy.

The entire car has 90,186 ft-lb of kinetic energy.

The total energy (car + flywheel) is 113,174.

About 20% of the engine's power was consumed in accelerating its own flywheel.

What happens to the energy stored in the flywheel? Most of it gets dissipated by engine braking as we shift to the next gear. If we shift like race cars, most of the energy is used up in friction as the clutch slips to match the engine speed to the next gear.

Perhaps this may be a factor in this apparent paradox.

I'm curious how you came up with the flywheel's kinetic energy. I calculated the moment of area as 0.5mr^2 = 0.5*30*0.5^2 = 3.75, then energy as E = 0.5Iw^2 = 0.5*3.75*100^2 = 18,750, where did you get the 22,988? (Just curious)

Kirk

I'm curious how you came up with the flywheel's kinetic energy. I calculated the moment of area as 0.5mr^2 = 0.5*30*0.5^2 = 3.75, then energy as E = 0.5Iw^2 = 0.5*3.75*100^2 = 18,750, where did you get the 22,988? (Just curious)

Kirk

The weight of the flywheel must be converted into proper mass units by dividing by the acceleration of gravity in which this mass was weighed.
When we say that something weighs one lb, it is understood that is was weighed on the surface of the earth, not on the moon or jupiter, and since weight = mass*gravity, we must factor out the earth's gravity by dividing the weight of the flywheel by the acceleration of earth's gravity, 32.2 ft/sec^2.
The flywheel has a mass of 30/32.2 slugs or .932 slugs. Slug is the official name for the basic unit of mass in the english system.

Angular velocity has to be stated as radians per second, not revolutions per second.
100 rev/second * 2*Pi =628.32 radians per second.

Plug in .932 slugs for the flywheel's mass and 628 radians/second for the flywheel's angular velocity and you will come up with an answer close to mine.

Anyway, the point is that the "flywheel tax" on the energy that the engine delivers in the lowest gears is not trivial and the best overall efficiency is a tradeoff between shift points that allow the engine to be efficient and the shift points that keep you from throwing energy away by accelerating the flywheel, alternator, harmonic balancer, and crank to high rpms and then mostly throwing their kinetic energy away when you shift to a higher gear.
In the higher gears, the car has a lot more speed for a given engine rpm and thus the ratio of flywheel energy to total car energy is a lot lower, that is, the higher the gear you use to accelerate, the lower the "flywheel tax".

Ah, right. thanks. The whole lb/slugs thing screws me up, I'm used to kg/N and sometimes you see lbf and lbm which makes it even stranger.

Kirk

I've had the scangauge for a week now. This is what I found out.

Under 15 mph in 1st or 2nd gear gets 5 to 8 MPG . The faster I can get to 25mph or 35mph in 3rd+ the better the MPG . 20 to 30 MPG while maintaining speed.

If the ECT is low, Neutral gives about 5mpg better then Drive below 25mph. When ECT is 190F they are about the same.

Coasting in the 30 to 50mph (4th) range with ECT at 190F, Drive gets better MPG , Neutral rolls father. No Dfco (edit: induced Dfco by downshifting to 3rd today)

I heavier foot is ok if the rpm's are kept below 1500-1750 rpm's.

I'm rethinking my thoughts on this. My newest idea is this:

"Shape" the acceleration. Super light from a stop, but gradually increase the throttle as speed and gears increase. It's not so much the style of driving, as it is the speed. Accelerating from a stop, you'll want to ramp up the throttle so you're hitting the same high-load point once you reach 35mph (or whatever) where you would be doing P&G.

Thoughts?

I'm rethinking my thoughts on this. My newest idea is this:

"Shape" the acceleration. Super light from a stop, but gradually increase the throttle as speed and gears increase. It's not so much the style of driving, as it is the speed. Accelerating from a stop, you'll want to ramp up the throttle so you're hitting the same high-load point once you reach 35mph (or whatever) where you would be doing P&G.

Thoughts?

That's what I've been using. Maybe it has something to do with the fact that you move from 1st to 2nd to 3rd a lot quicker than 3rd to 4th to 5th. If you were to maintain high load in lower gears this means choppier accelerations, and more throttle modulation (this is a no-no in DWL). In higher gears the time it takes to move between shift points is longer, so this effect is not as pronounced. I don't know if this theory is sound at all, but it might be part of an explanation...

Kirk

I've been testing this lately and Wayne is exactly right. From a stop, bring it up slowly and lightly. At speed, in a P&G routine, that's where you use the heavy throttle. 2 different applications, 2 different answers.

I'm not quite sure what you mean by heavy throttle. What I have found in the FIT is that the proper technique depends on how warm the engine is, and that the proper acceleration on the pulse is a lot like the feathering techinque you described some time ago.

What I do is start the pulse with a moderate throttle, then "feather off" a bit halfway through the pulse. This works better the warmer the engine, and i can "feather" earlier, the warmer the engine.

Larry

hmmmm... so you start the pulse on the heavy side and taper it down to light throttle at the peak? I've been doing the opposite for my pulse. Watching the LOD gauge, you have to add a bit more throttle as you go up, to keep it at a constant reading.

What I meant was to extend that all the way down to a stop, through all the gears. Something like this:
stop - 0 throttle (of course)
1st gear - minimum possible
2nd - 20% throttle
3rd - 40%
4th - 60%
5th - 80% throttle, just like used in P&G

Andrew, I also start light and lean into the pedal as speed increases to maintain the load value -- only I will actually do it on each gear (between shifts) as well. I'm always chasing that load.

Sean, thanks. That's good to know. I'll have to check - I may be doing that already. Keep in mind that you'll be in each gear 1.5-2 times longer than I will, with your crazy-tall gears and my crazy-short ones. It probably makes a little more sense to do that in your case.

ok im still trying to figure out how some do it , but heres my question about after bumping start the car then going to accelerate, what gear do you guys with civics like mine drop to i usually drop to 4th and rev to about 2500 or 2800. Is that what most are doing or are you reving higher and staying in the lower gear longer or not? thanks

ok im still trying to figure out how some do it , but heres my question about after bumping start the car then going to accelerate, what gear do you guys with civics like mine drop to i usually drop to 4th and rev to about 2500 or 2800. Is that what most are doing or are you reving higher and staying in the lower gear longer or not? thanks

What speed are you going when you do this? 2500 to 2800 RPM is too high, you should be in 5th at that speed. You usually want to stay below 2000 RPM if possible.

Kirk

Since you have the same series car as mine...

You need to keep the rpm lower than that. If it's above 40, I only ever use 5th. My daily commuting rarely exceeds ~2200 rpm. The only time I exceed ~2500 is on highway trips, and then only at the peak of a P&G cycle. If the gears allowed lower rpm, I would use that.

You can gently accelerate in 5th from as low as 30mph.

My thoughts when people were talking about their pulse was they were dropping down a gear to accelerate faster but it seems like for me, on the highway that is, I should bump it in 5th, then put it in 5th and accelerate back up to speed using about 60-75% throttle?

So even when at a lower speed i should try to keep it at the lowest rpm, without bogging, to get back up to speed. Keeping the rpms where i would normally shift as if coming from a stop, but when pulsing more aggressive throttle usage? hope that makes some kind of sense

My thoughts when people were talking about their pulse was they were dropping down a gear to accelerate faster but it seems like for me, on the highway that is, I should bump it in 5th, then put it in 5th and accelerate back up to speed using about 60-75% throttle?

Yep, you want to be in 5th, and you should be around 75% LOD, which on my car is around 50% throttle. Andrew, does this sound right for the Civic?

So even when at a lower speed i should try to keep it at the lowest rpm, without bogging, to get back up to speed. Keeping the rpms where i would normally shift as if coming from a stop, but when pulsing more aggressive throttle usage? hope that makes some kind of sense

Yep, that's it.

Kirk

I usually look at LOD, so I'm not actually sure what the TPS is. :o I aim for 80 LOD.

... or, whatever high-ish load will get me to peak speed near my target point - one that will allow the best glide from there on. The top of a low hill works well.

ok so yesterday i was driving I-83 N in PA which is a rollercoaster like road like wayne puts it , and i was trying the technique driving with load for my pulse at 70-80% and i can see it getting better mileage doing so, but jsut so im not going crazy it is still rather slow and at that LOD im at maybe 25-30tps at most.

I am still a bit disappointed in my efforts for this tank with about 550 so from what the scangauge said i was getting abouot 46.2 mpg, which to me isn't enough!

Any more tips you could offer? Its seems also accelerating up to my set speed slowly is really taking a longgggg time but if that has been proven hopefully the results will pay off soon.

If you're used to shifting at 3500 RPM and having it nearly matted, then shifts at 2000 and 80% load will seem slow for acceleration. However, you're going to be getting better mileage. Remember that it's all the techniques put together that give you the good numbers, not just one of them. Keep practicing and you'll see your numbers rising. Have you calibrated the SG yet? If you haven't run it through a couple tanks, don't count on it being accurate.

Most of the tips you can pick up by reading "Beating the EPA" and reading past threads, there are so many different tips for very specific situations, that it takes a while to learn them all.

Kirk

Since getting my SGII about a month ago, I've been trying various regimens of P&G - it is certainly best to make the pulses cover as little ground as possible. I've noticed that under acelleration in 4th going from 35 - 45 mph, that the MPG hovers in the 12 - 20 mpg range, and that a heavier foot doesn't lower it too much (what's the difference between 8-10 mpg over 5 seconds vs. 15 mpg for 10 seconds with a shorter glide?) One thing P&G does, though, is to up your trip average speed a bit.

Anyway, I'm surprised to see my tank MPG has actually gone DOWN since getting the SGII. Before that, I used my ear to sense the load on the engine and just tried to be as gentle as possible. However, I think I'm building up a database of the correct techniques to use with specific conditions, and hope to see some improvement. My next target is a 38MPG tank in my Ranger...

fixedgear, I've been watching LOD more and more for gauging acceleration rates, aiming for 75% (floats between 70-80) and in 3rd or 4th I usually end up digging in a little deeper throttle to maintain the LOD reading. My shift points are generally around 1800-2000 rpm, if I'm going up to highway speeds, otherwise I will shift at lower revs. There are times in heavy traffic that I'm cruising along in 5th gear at under 20mph at about 700 rpm.

Absolutely you can do 38 mpg in that Ranger!! Your techniques will end up being a little different than mine, since your engines torque range is different. TorqueNada's peak torque is at 2400 rpm ... well 'peak' is still pretty 'meek' in this truck ;) - 0-60mph in 26 seconds oh yeah baby race me!!

Sorry i should have been clear that i def am one with hypermiling and have been for quiter a while, in that i never shift above 2200rpm at the very very most and have to say you are right about the scan gauge and my tanks since i don't drive alot so there isn't a ton of info .

One thing i did remeber from my last fill up saturday was that i got 56.4 mpg on my 35 or so mile trip, which isn't bad considering the car had my gf, hatch full of stuff to weight the car down so that didn't help i don't think.

just to gauge how other do it what kind of LOD do you have when acclerating from a stop or say getting on the highway, as i am trying ot keep that as low as possible along with my tps reading.

I use 75-80% LOD for acceleration. In my car, 70%-80% is a big jump is a big jump in acceleration, you can definitely feel it. I shift at 1800-1900 RPM, the diesel has lots of low-end torque.

Kirk

so from a stop you are hitting between 70 and 80 LOD? I jsut want to make sure i am getting that right, if not what would most suggest and what do most abide by?

Yep, although through 1st and 2nd it's so quick between shifts I don't bother looking down.

Kirk

Thanks, Slowhands, for your words of encouragement. Now when I see Rangers, I think "hypermile vehicle in a pig's clothing"! (Unless they're V-6 automatics with 4wd...)

When I first started using more p&g, I tried brisk accellerations at higher RPM to get power over a short time. Seemed like a good idea, but I saw my MPG go down, but not much. Now, I'm trying using more DWL between pulses if the terrain dictates, which looks promising.

OK, where do I find information on the engine's torque/hp curves for my 2002 Ranger? Might be useful information.

I tried calibrating the SGII at this morning's fillup and han to dial it down about 40% to get the fill qty correct. Now it shows me getting insane mileage going up steep hills, so I'll have to fix that. Perhaps reset it to factory, or re-adjust it. (Should have written the adjustment factor down...)

Now that I'm looking at LOD, I guess that's a relative value that can't be easily compared car-to-car. Mine shows something over 20 when coasting with NICE-ON (the TPS shows 16 in the same condition). But it seems useful for running DWL.

Thanks, Slowhands, for your words of encouragement. Now when I see Rangers, I think "hypermile vehicle in a pig's clothing"! (Unless they're V-6 automatics with 4wd...)

Well, I don't have 4wd, but that's all my 2000 Ranger is missing. I just started hypermiling, and so far I'm mainly just DWLing by keeping TPS < 30 (flat 55 mph takes about 26) and coasting in neutral whenever feasible. Most of my driving is 45-55 mph.

Accelerating from a stop at TPS=29 (about as slow as I can stand) gives an LOD of 67-70 as I accelerate. The automatic goes through the gears so quickly, it doesn't seem significant to be concerned about RPMs.

I don't have any MPG figures yet, but it looks like I'll be doing good to get to the high 20's. (head hanging in shame).

Lane

I have been doing P&G for a few months now doing 60 mile trips. I have been using 80% LOD over a 50-60mph range. The mileage during the pulse is around 12 mpg.

I have been experimenting with 50-60% LOD (really feathering the throttle) over the same range and overall mpg seems better. The mileage during the pulse is around 20 mpg.

I have to try for an entire tank to be sure if it is better for me.

It seems to me that this may be vehicle specific. The Versa 6 speed has terrible gearing.