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Hi all!

7 mile city stop and go commute to work from Chicago to suburb. Takes 30 minutes. Have a couple of longish glides, but only if I get lucky with stoplights. All city streets. May stop signs.

I have tried and failed to get 30+MPG on pulses. I am clueless.
Can some one treat me like a 5 year old and wolk me through the process of tdoing this with a stock 2005 Prius (have engine block heater)?

I've read many forums and chat sites, but do not have any extra fancy meters to attach to tell me RPM and/or VO etc,e tc.

Thanks In Advance,

KenO

Welcome to CleanMPG!

I don't drive a Prius (but need to take a few more spins in one), but krousdb is a master at this - ditto for hobbit

Welcome kenoarto! I don't drive a Prius either...yet. Krousdb and hobbit and a few others I can't think of at the time are masters at it. Even though he doesn't drive a Prius, Wayne(xcel) would be a person to visit if you were in the far northern suburbs of Chicago.

I'm thinking you have to shorten the pulses

Hi KenO:

___Welcome to CleanMPG and the following may help?

Pulse & Glide plus Warp Stealth in the Prius II for maximum Fuel Economy … (http://www.cleanmpg.com/forums/articles/t-pulse-and-glide-plus-warp-stealth-in-the-prius-ii-for-maximum-fe--1224.html)

___That articles pics are all you need to duplicate with your right foot and your set. If you have ever visited a Hybrid Group Meet, there will be individuals there that can run you through a quick Hypermiling clinic and once you see P&G in action; you will understand both its implementation and its implications. The numbers get stupid high real quick. Trust me on this as the Prius II can be taken beyond 120 mpg’s with the right course, the right setup, and the proper temps and conditions ;)

___Good Luck

___Wayne

I justs made a blithering idiot our of myself trying to talk with someone in my office who is writing a series of "green" articles for our magazine.

At some point I blurted, "obviosly I have plenty to learn about this subject, but I can't believe it's only been a year and I'm complaining that my gas milesage has gone down from 49MPG during the summer to 44MPG during the winter--that's more than twice what I was getting from my 93 Nisaan Altima."

Thanks all for your input, I just joined this group after a nice year with priuschat.

Wayne, I bow very low at your feet.

Please be patient here, I really need to disect the pulse:

“Pulse” is any acceleration from a lower speed target at a rate to keep from drawing off the pack while also filling the pack (Green Arrow from the MGSet to the Pack on the Energy Monitor screen). You do not want to see Orange arrows from the MGSet to the Wheels on the Energy Monitor screen."

> This seems to be random while accelerating. I've tried more and less gas.

Our intent during the “Pulse” phase is to get up to a top target speed less then 41 mph in which you can quickly and smoothly transition to the “Glide” phase. Any top speed target will work to fit a given traffic condition as long as you maintain less then 41 mph for the highest FE .

>Got it.

That was the explanation but how do you actually “Pulse”?

> I obvioulsy use too much gas while pulsing. City stop signs and lights happen every 1/4 mile. My commut involves no speed limit above 35 (but there are two longish patches where I pulse it up to 41).

Using a 30 mph to 40 mph band as an example, when you are cruising along at 30 mph, you step into the accelerator just enough so as to not see assist from the pack (as described above) and fast enough to maintain an average “Pulse” rate of your choosing.

> I suppose I need to feel the kind of accertation. Is it a punch or a super slow or what? How do I find 40MPG pulse?

You can control your “Pulse” rate of acceleration but you do not need to maintain an exact rate as seen in the pics below. A 20 MPG average “Pulse” rate may include an initial 17 MPG rate when you first start the “Pulse” and maybe 23 MPG “Pulse” rate when you hit your top target speed before you transition to “Glide”.

> Now wait I feel a headache comming on...so 17 to 23MG is what most hypermile city drivers (an oxymoron I know, but I'm trying) are using?

For a 40 MPG average “Pulse” rate, you might see a 36 MPG “Pulse” rate when you begin your “Pulse” and a 44 MPG “Pulse” rate just before you enter your “Glide”.

>44MPG pulse sounds great, I this a fast or slow accel? I don't have enough time to glide if I accelerate slowly.

To recap, you gently step on the accelerator enough to get the ICE to spin up and provide propulsion with the energy screen showing ICE power to the wheels and power through the depicted MGSet to the pack while the digital iFCD readout is showing anywhere between 15 and 55 MPG for the acceleration back up to 40 mph or less.


>And here I am in a connundrum again...So for 1/4 mile what's the plan?1/2 mile? 1 mile...(not that I often get that lucky).

Thanks In Advance

kenoarto- It sounds to me like you may be overanalyzing things just a bit. There is more than one way to skin the proverbial cat and it will take some experimentation to decide which is best for you.

On the pulse, the key is not to draw off of the pack. There is a fairly wide range over which this occurs, and it starts as soon as you have stepped applied enough accelerator pressure to light the ICE. The end of that range comes at the high end, where the computers decide that you want more power than the ICE can efficiently provide you by itself. The state where you are accelerating and charging tends to lie on the gentle end of the pulse spectrum. Once you get beyond that you will notice a range where energy is flowing neither to nor from the battery pack. (This is commonly referred to as a "dead band" pulse though I have no idea where that nomenclature came from.) I believe that this variety of pulse is just fine for day-to-day driving.

I'd like to throw in a couple of comments.
1)City driving with 1/4 mile b/w lights will make a 'normal' P&G difficult to achieve. You simply don't have enough distance to really make practical use of the cyclic nature of P&G.

2)That is not to say that the basics of the technique can't be employed to help improve FE.

3)Anticipatory driving is probably the single most important thing you can do in city driving...avoid unexpected slow downs....stay off the brakes when possible. Don't tail-gate.

4)Consider an EV button. In my experience it can be difficult to get up to 35mph...the speed necessary to get into stealth (most of the time)... If you know a stop is coming and the ICE hasn't shut down the EV button can force that condition so you're not burning gas by idling.

5)Don't get hung up on instantaneous mpg numbers...I generally accelerate at somewhere b/w 1700-2300 rpm...this usually equates to a gradual but not sluggish rate of acceleration. I'd say mpg is generally around 20mpg during that phase, though it's variable to some degree.

6)Consider blocking your grill in the winter...longish stops at a light, long glides, and etc. can allow the ICE to cool down below ideal operating temps...you won't be able to get a good glide until and unless the ICE is warm enough to permit it.

Hi Keno:

___Both Brick and Efusco own Prius II’s and know the ins and outs of the process very well under a variety of conditions. It does sound like you are trying to force a particular rate and range into your std. light to light distances of your daily commute. I have said this on numerous occasions, don’t chase the FE but let it come to you when it comes to taking the Prius to obscene levels. Take it very slow and let those glides extend. Afterwards, you will be amazed. Setup is critical this time of year with the winter temps what they are. Prius’ act very differently in 55 and below temps then when it’s a beautiful 72 + and sunny. A block heater will help you move away from that first 5 minutes of < 35 mpg hit pulling down your total daily and tank averages some. The Radiator block willl help maintain the ICE bay and coolant temps as Efusco noted. Higher pressures in the GoodYear Integrity’s help with RR which helps extend glides and lower the amount of power needed to accelerate to a given target speed. Do not use a 40 mph target as your goal. If traffic allows, use whatever fits. A 15 - 30 mph range with a higher accel rate in heavy traffic may suffice as that will fit a ¼ mile to ¼ mile stop light to stop light scenario with a little anticipatory timing thrown in to catch maybe ¾ of more of those lights green. Don’t assume a given accel rate and range is optimal in traffic. Just go with the flow below 40 mph and have some fun out there. Be very careful however as both the Consumption and Energy screens can be a bit addictive for one so new to the P&G routine. She is very forgiving and you will definitely improve your lot as temps increase this coming spring.

___Lastly and probably most fortunate, you live in the Chicago area :D Tom and I will be heading up to the Madison Hybrid Group meet this Saturday morning. You are more then welcome to come and we will be more then happy to provide some clinic time as it is always great to see a new driver see some great numbers for himself. In some cases, sub-practical speeds may not fit the traffic pattern depending on your specific commute.

___Stop light to stop light is where I believe the Prius II is at its best although I know many that will disagree.

___Good Luck

___Wayne

KenO,
Let me try to help:

Meet me at the next Chicagoland Prius meet-up.

Wasn't that easy? ;)

You may not be able to do this until warmer weather, but one
thing that helps is to *listen* to the engine. You know how
a typical automatic-transmission car sounds off the line, from
idle to fairly reasonable acceleration? That's sort of what
you want to hear in the Prius, too. Engine RPM comes up a
little but not to a ridiculous range. If you have musical
sense and can get a feel for the "note" of the idling speed,
I'd say go up between another fifth and another octave. Guess
what, that's between 1500 and 2000 rpm. Anywhere in there
is good; just try avoid feather-footing trying to be *too* gentle
because a> you'll drain the battery more off the line and have
to make it up, and b> you'll be "loafing" the engine in an
inefficient range. In short, *use* the engine to accelerate,
where "use" means get somewhat serious about it, but try not
to stay glued to an arbitrary number on the MFD. Then once
you get going, then fool with gliding. Once you get used to
that pattern, a little bit of "vroom" followed by that wonderful
silence broken only by tire noise, it'll become natural.
.
I would also advocate looking into some sort of instrumentation,
just because it *does* make various jobs easier. But it's still
important to just get that butt-feel of how the car works.
.
_H*

Evan and Wayne, I bow to your vast weatlh of knowledge, and success,
Notes interspsered below:


1)City driving...will make a 'normal' P&G difficult to achieve.

> Ya but I was soooo close to 50MPG. I saw many full bars during the summer. Almost had a couple of 500mpg tanks (490s)

2)...the basics of the technique can't be employed to help improve FE.

I'm lookiing for improvement, not the Japanese record!

3)Anticipatory driving is probably the single most important thing you can do in city driving...avoid unexpected slow downs....stay off the brakes when...Don't tail-gate.

>Yuperoonie. I know my posts read like I'm a lead foot. I'm really not! I've grown use to my share of SUVs tailgating and then gliding past them at stoplights.

4)Consider an EV button....it can be difficult to get up to 35mph...the speed necessary to get into stealth (most of the time)... If you know a stop is coming and the ICE hasn't shut down the EV button can force that condition so you're not burning gas by idling.

> Huh!?! I've read the EV button makes little, if any, difference. Do you really think this may be the solution for city driving? Sounds like a fun too!

5)Don't get hung up on instantaneous MPG numbers...I generally accelerate at somewhere b/w 1700-2300 rpm...this usually equates to a gradual but not sluggish rate of acceleration. I'd say MPG is generally around 20mpg during that phase, though it's variable to some degree.

> Ok I'll aim for that tomorrow! Alas, I have to stop for gas. This tank: 43.6MPG helped greatly by two trips to the suburbs with some highway miles at 55MPH. Less than 400 miles :-(

6)Consider blocking your grill in the winter...longish stops at a light, long glides, and etc. can allow the ICE to cool down below ideal operating temps...you won't be able to get a good glide until and unless the ICE is warm enough to permit it.

> Been there, done that. Have intalled the foaom tubes in the hood grills, have the block heater too. Got me up from 12 to 25 first 5 minutes (normal in the summer). Stock tires are at 42/40. Mileage is just under 10K.



Today, 05:36 PM

xcel
Senior Member

...Both Brick and Efusco own Prius II’s and know the ins and outs...

...trying to force a particular rate and range into your...daily commute...don’t chase the FE but let it come to you when it comes to taking the Prius to obscene levels. Take it very slow and let those glides extend. Afterwards, you will be amazed...

Very Zen, but I can't wait to see how YOU do it. Actually I'm just looking for something new to try.

Prius’ act very differently in 55 and below...A block heater will help...first 5 minutes of < 35 MPG...Radiator block willl help maintain the ICE bay and coolant temps...Higher pressures in the GoodYear Integrity’s help with RR which helps extend glides and lower the amount of power needed to accelerate to a given target speed. Do not use a 40 mph target as your goal. If traffic allows, use whatever fits. A 15 - 30 mph range with a higher accel rate in heavy traffic may suffice as that will fit a ¼ mile to ¼ mile stop light to stop light scenario with a little anticipatory timing thrown in to catch maybe ¾ of more of those lights green. Don’t assume a given accel rate and range is optimal in traffic. Just go with the flow below 40 mph and have some fun out there. Be very careful however as both the Consumption and Energy screens can be a bit addictive for one so new to the P&G routine. She is very forgiving and you will definitely improve your lot as temps increase this coming spring.

___...Tom and I will be heading up to the Madison Hybrid Group meet this Saturday morning...we will be more then happy to provide some clinic time as it is always great to see a new driver see some great numbers for himself. In some cases, sub-practical speeds may not fit the traffic pattern depending on your specific commute.

___Stop light to stop light is where I believe the Prius II is at its best...

> Really?

___Good Luck

thanks!

I wanted to make, but missed the last Chicagoland meet.

When is the next one?

Ken,

The next Chicago Hybrid meet is ...... sometime this year. Your route sounds similar to mine, and I'm at 57MPG with 540 miles on this tank, so let me give you some advice. In the city driving we do try to accelerate deadband or with charge to the battery. But the important thing, which Wayne touched on, is you can not do classic P&G. Try this instead;

You know how far to the next traffic light

You know how far you can glide until you hit a speed you feel you have to accelerate

Pulse 1/4 to 1/3 of the way to the next light, be at the speed you feel you need to be at to glide the other 3/4-2/3 and start your glide

It does not matter what your top speed is or your speed after you finish your glide, what matters in the city is to get into your glide.

Example; Next light 1/4 mile away (2 blocks), speed limit 30 MPH, accelerate 1/2 block up to 30 MPH or what ever speed you need to glide to the light, glide 1 1/2 block to light. Since your gliding 1 1/2 blocks out of 2 that means 3/4 of your travel is without engine so if your acceleration is not perfect your sins have been covered by a long glide.

Wayne

While I don't promote the EV button as a FE tool in general, there are absolutely situations where it can help. City driving, when used properly, is one of those situations. I don't intend that you'd use it for driving b/w lights, but to shut off the ICE when approaching a light can help. IOW, usually to get into stealth you have to hit 35mph then back off the accelerator... if traffic is fairly heavy and you can only get up to 30mph (or that's the speed you're at in your 1/4 way to the next light routine like Wayne described) then you can force the ICE off with the EV button and glide on to your stop.

Once the light changes, however, I recommend hitting the button again and allowing the ICE to do it's thing.

Listen, city driving, in my experience, takes a relatively long time to get "right". It helps to take the same route, learn the timing of the lights, the patterns of the traffic, etc. to aid in your technique. You may be able to learn to glide from light to light without ever needing to come to a complete stop (ideal situation btw) once you've figured out the timing of the light. In other areas there'll simply be little to nothing you can do as traffic will force undesired stops and starts....even in these areas, though, the EV button could be your friend to prevent the ICE from coming on and/or to shut it off if you have to use it.

Example; Next light 1/4 mile away (2 blocks), speed limit 30 MPH, accelerate 1/2 block up to 30 MPH or what ever speed you need to glide to the light, glide 1 1/2 block to light. Since your gliding 1 1/2 blocks out of 2 that means 3/4 of your travel is without engine so if your acceleration is not perfect your sins have been covered by a long glide.
Wayne, do you practice or suggest the use of [N] (Neutral) in the glide? I have found, especially in cold weather, that I can achieve higher instant MPG by slipping into [N] and gliding. Sometimes, the engine will simply not shut off otherwise: no true glide, no stealth. But when I go to [N] the display shoots up to 99.9. However, sometimes and paradoxically if I'm still in [N] when I reach the light, the engine will be running and by going back into [D] at the light the engine will shut off.

Tony, the ICE will always stay running if it was running when you put the car in Neutral. Likewise it will always stay off if off when you put in neutral. Fuel consumption is low, hence the higher instantaneous mpg reading. This is where EV is a better option than neutral. I, personally, don't use or recommend using neutral.

Tony,

Never neutral, tried some but it just doesn't seem to work right. When it's really cold and you can't get into glide and your SOC is good then either the engine or Cat needs to be heated. Rather than fight it I back off to the highest MPG I can and keep some speed to let the car do its thing. After it gets warm enough it will glide again. And turn that heater off.

Wayne

Did you know a block heater will get your coolant temps up and help with that problem?

Averaged 54 MPG yesterday! I thought this couldn't be done! And it was 27 degrees outside--I have blocked the radiator grills with pipe insulation.

Filled up before I got on the expressway($1.99 in Wilmot Wisconsin). Cruise controled for 20ish miles at 69mph--bars were averaging just below 50mpg. Then some jerk started tailgating me in the right hand lane, so I slowed down to 61mpg (even tho the two left lanes were wide open, this idiot continued to draft me). When I got home...60+ miles...54.3mpg!!!

Now if I could only figure out how to accelerate from a dead stop without wasting gas during my normal city commute.

Hi Kenoarto:

___54 + @ 60 mph in below freezing temps is fantastic! Keep up the great segments and when summer comes, I am sure we will be hearing a lot more about your exploits ;)

___Good Luck and congrats.

___Wayne