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Discussion Starter · #1 ·
I noticed that in Economy mode that the engine lugs badly when accelerating. This uses more batteries and thus more fuel to recharge them.

I have improved my MPG form 41.5 to 44 just by hitting the paddle shifter once or twice when I need to get the car up to speed.

In my commute to work the averaged hwy speed is about 50mph with a lot of 40-60-40 speed changes. The quick down shift gets me back up to hwy speed faster with less use of the batteries. So I'm back off the gas sooner and getting the mpgs back up.
Works on hills too. I think Honda could reprogram the CVT to do this in Economy mode and that would help there EPA ratings.
 

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Same w/ 6mt.. It's got indicators that tell you when it thinks you should shift. I was listening to the car. I finally decided to drive the way I want and it's the same observation you've made. The car wants to bog down the engine too much. Once I started leaving it in a lower gear for longer, I had more power and better MPG.
 

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Discussion Starter · #4 ·
would just leaving it in normal and then switching it to econ once you started cruising on the highway or wherever have the same effect as downshifting?
I tried this also but the transmission doesn't change modes quick enough.
I will leave it in normal if I am doing a lot of starts and stops and entering the freeway. but once I get to cruising speed I change to Econ and just down shift when needed.

I also use normal mode when i see the batteries getting near the half charge mark.

Again my average is 44mpg but on just the hwy I have managed 49mpg
 

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the reason they do this is that they assume you will accelerate VERY slowly in eco. should you actually increase speed that slowly, then you will maximize efficiency. remember, eco is intended to allow you to obtain max efficiency, hence retardedly slow acceleration.
 

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I've experienced poorer gas mileage from drives in which I downshift 2 gears while accelerating from stoplights in the suburbs. Perhaps I'm doing it wrong though. I am hitting the gas while accelerating to get up to speed as quick as possible. Perhaps downshifting while still maintaining a smoother acceleration would work better?
 

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the reason they do this is that they assume you will accelerate VERY slowly in eco. should you actually increase speed that slowly, then you will maximize efficiency. remember, eco is intended to allow you to obtain max efficiency, hence retardedly slow acceleration.
True until you get over 3K revs, I was coming of a roundabout floored the accelerator, changed gear between 5k & 6k revs, never droped below 3K revs and it felt as though it was in normal. I was shocked / surprised when I realised I was eco......

shocked eco didn't bog down as it does around 2k revs. surprised eco could accelerate and returned marginally better MPG when I began to cruise.
 

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yeah this works!

I tried it on my way home from work tonight and easily moved up into the low 40's mpg.
I have a tough commute that is almost all hills, and have been trying to figure a way to tackle the hills in eco mode. The method is proven if you watch the eco guide bars. When beginning to climb a hill, you will see the assist max out. Shortly after that, the CR-Z will begin to try to maintain speed, but it's lugging. The eco guide bar begins moving right indicating inefficiency. But if you downshift the eco guide bar moves back toward the center. Efficient hill climbing!
Thanks for the great post dntower85:thumbsup:
 

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can i get a paddle shifting for dummies lesson. looking at improving my MPG. never driven a manual transmission in 30 yrs of driving experience.
peace out
Do you have a manual or CVT?

In the CVT downshifting means you are revving the engine higher which can be a good thing if you want to climb a hill and not drain the battery. Upshifting will lower the engine revs and is useful after cresting a hill since the transmission is a little slow to lower revs on it's own.
 

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How does downshifting increase mileage?

Could someone please explain this concept to me? It sounds counter-intuitive. Revving up the engine more should be burning more fuel (gas or electric) while keeping the speed down, and the engine would be subject to more wear.

I just don't understand! The only thing one should be getting from downshifting is better acceleration, but that should be about it.

Thanks!!
 
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Lot of hills in my area. I have been alternating between NORM and ECO for hills and accelerating and noticed an improvement over ECO alone. The only thought I had been giving the shift paddles was how they interfere with seeing the blinker and wiper controls.

I will have to try leaving it in Eco, watching the guide bars, and manipulating the paddles to keep the guide bar toward center. Makes sense.
 

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Could someone please explain this concept to me? It sounds counter-intuitive. Revving up the engine more should be burning more fuel (gas or electric) while keeping the speed down, and the engine would be subject to more wear.

I just don't understand! The only thing one should be getting from downshifting is better acceleration, but that should be about it.

Thanks!!
The engine has a power band where it is more powerfull at the expense of a little to a lot of fuel economy.

The powerband seems to be around 3k to 4.5 on the tach.

So if you are climbing a hill at less than 2000 rpm, the engine lugs and works too hard to maintain any fuel economy.

So if you "downshift" to make the engine operate in the powerband, you get up the hill quicker and then can resume fuel conserving driving techniques.

If you ever rode a multispeed bike, would you climb a hill on the tallest gear? Or would you change to a lower gear that is more efficient?
 

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The engine has a power band where it is more powerfull at the expense of a little to a lot of fuel economy.

The powerband seems to be around 3k to 4.5 on the tach.

So if you are climbing a hill at less than 2000 rpm, the engine lugs and works too hard to maintain any fuel economy.

So if you "downshift" to make the engine operate in the powerband, you get up the hill quicker and then can resume fuel conserving driving techniques.

If you ever rode a multispeed bike, would you climb a hill on the tallest gear? Or would you change to a lower gear that is more efficient?

Generally agree :)

But efficient really means the "middle path" no? It is not necessarily more fuel efficient. It is the best of both worlds between being fuel efficient and speed. But, if I don't care about speed on a normal commute, wouldn't I be more fuel efficient with the CR-Z in economy mode without down shifting?

Thanks!
 
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Generally agree :)

But efficient really means the "middle path" no? It is not necessarily more fuel efficient. It is the best of both worlds between being fuel efficient and speed. But, if I don't care about speed on a normal commute, wouldn't I be more fuel efficient with the CR-Z in economy mode without down shifting?

Thanks!
Actually, Efficiency is defined as " achieving maximum productivity with minimum wasted effort or expense."

It may help you to think of the "middle path" with regard to where in the engines rpm range does it most efficiently move the weight of the car forward (productivity) for a specific amount of work or fuel given (effort/expense).

The engines rpm power curve (aka: power band) is shaped like a bell. Look at a bell from left to right. There is a front side of the rpm power curve (think acceleration from zero to cruise since it takes more fuel to get the car up to speed than it does to maintain speed). There is the top of the rpm power curve (think cruise and this is the point where the vehicle travels the most distance over time for the least amount of fuel required). And lastly, there is the backside of the rpm power curve (the point at which introducing more fuel [work] no longer results in extra speed [productivity] or simply, the point at which added work results in less productivity).

You can see this concept in action just by selecting the defrost to "on" so that the car will not shut off while you are idle. In this case, you have placed a load on the engine but the car is not going anywhere. Sit idle long enough and you will begin to see your mpg's reduce. This is the backside of the power curve because you are burning fuel (adding work) but you are not going anywhere (no productivity).

A similar situation is occurring when you place a load on the car, such as a hill, with the cruise control set and the car in the ECON mode. The car senses that you are slowing down but the ECON mode is too slow to react. This results in the car having to work harder for longer because it must BOTH accelerate back to AND maintain the speed you have requested for the added load the hill is placing on the car. This is the front side of the power curve. You had to accelerate.

In the NORM mode or by downshifting the car manually, the engine is better capable of maintaining the vehicles speed because it reacts to speed reductions more quickly. This means the engine is working less because it must only work to maintain speed instead of trying to both accelerate back to and then maintain speed.

You see,,, in terms of the efficiency definition, this last example is the "middle path" you referenced because you get the most "production" for the least amount of "work." If you truly do not care about speed, I challenge you to let the car sit idle in the parking lot for an hour before your commute home. I think you will quickly realize that speed (the ability to maintain it) is an important part of efficiency.

Hope that helps.
 

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After reading this last night I tried it on my way home. Getting onto the on ramp of a major hwy here the car in econ mode is very slow to respond to me pressing down on the gas pedal. Downshifting into third going 50 mph (wanting to go 60) did several thing right off;

1. Raised the cars RPM
2. Made the Efficiency scale drop to the center line in ECO Display
3. Stayed in the lower gear for about 1 second then returned to normal
4. Made the car take off! Its like little shots of Turbo. Went from 50mph to over 60 very quickly.
 
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