The only indication is that your iFE is pegged at 100. The autostop light does not flash, and your rpms do not drop.

As far as acceleration goes, it is best to accelerate moderately. Too slow or too fast, and you won't be getting optimum FE. If you have not already, I would reccomend reading Tarabell's article. (I think I need to re-read it, as it's been a while )

 

I highly doubt that. The only time I can ever get bars of assist above ~35mph is on a sustained downhill and it requires some fancy footwork (and I can't sustain it for any length of time).

I think it's important to not get hung up about electric mode. Our other hybrid is a Mariner with the Aisin eCVT (nearly identical to the Prius') that can drive without the engine on below 40mph. While that car is really good in stop and go traffic (when warm), the ability to achieve 0 G/Mi only happens below 40, and you have to know the tricks to get the engine to shut off.


With the HCH, I can hit 0 G/Mi whenever I want to, at whatever speed I'm going--all I need is some momentum and the right foot pressure. I think it's an easier to control system, and it is a lot more versitile. I would never trade the ability to glide at any speed for the ability for the engine to shut off at low speed (although I do wish the HCH had about 70hp of electric power and could creep in auto stop just a little).

 

Prius can run fuel-cut mode above 42 mph, where engine has to spin, but we see 0 G/mile.
I'm surprised to see the MMH is different.

Ken@Japan

 

Yeah, but the MMH is engine braking when in fuel cut mode. The only time I have ever gotten the fuel cut to be worth anything is when I was going from Idaho Springs to Denver on I-70 (a vertical drop of ~3,000 feet) where the car had enough momentum and downhill to keep moving. With the HCH, I can glide for miles on a slight downhill because there is very little engine braking.

How does this work in the Prius?

 

Prius does the same thing.
A slight touch of accelerator pedal is good for no or very little engine braking.
However, we need a certain amount of energy to spin the engine, so we see the 42 miles per hour barrier for fuel economy.
It is impossible to see more than 100 mpg average on highway, but we can see it below that speed.
http://www.cleanmpg.com/forums/showthread.php?t=1793

Ken@Japan

 

I seem to see something different in my 06 HCHII, when I am very careful with the throttle (no sharp movements) and on either a flat road or a slight downhill my car seems to go into some kind of coast/electric mode. My mpg's actually slowly go to zero in a about 6 seconds, I am guessing the electric motor is just being used to counteract the friction of moving the engine components. I usually can't keep this up for very long before I either have to slow down or speed up, making the car go back to normal.

 

Chris: For some reason, when you are gliding in the HCHII and are using no regen/acceleration, your iFE display will go down (and sometimes back up and down...). No one is really sure why. It does not affect your average MPG, and when you are doing it, you are using no gas. Do a search on this forum about it. Many call it the iFE "Samba".

 

This happen to my car as well. My iFE drops to 0 km/l. It could stay there for quite a while as long as I am careful not to increase or decrease my right foot pressure on the accelerator.

I also noticed that if I drive at around 50 ~ 70 km/h ( approx. 30 ~ 45 mph) on a relatively flat road, iFE could reach and maintain at around 37.5 km/l ( approx 85 mpg ) or higher.

Currently able to run on Electric only at speeds 50 km/h and below ( approx. 31 mph ). I am trying to run on electric only for speeds above 50 km/h. Why? because driving at speed between 50 ~ 70 km/h, ICE still drinking 37.5 km/l. In Electric mode, no gas needed.

I understand that the batteries need to recharge somehow... either from ICE or REGEN. And I get it REGEN instead of burning gas. I find it relatively easy to get into REGEN mode in urban areas ( on city & highway as well ) driving. As soon as my right foot is off the accelerator pedal, iFE shows 50 km/l ( approx. 117 mpg ), which means all valves are closed, no fuel used - please correct me if I'm wrong. And CHRG meter bars lights up ( if batteries are NOT fully charged ).

I managed to get 52 mpg for my last tank - not bad considering URBAN driving with 40% city highway. However, I am trying to improve that as I see many are getting much better mileage than 52 mpg... of course noting that there are so may parameters like driving on different terrain and driving style. I believe that if the CIVIC hybrid could run on ELECTRIC only at slightly higher speed ( say 70 km/h = 43 mph ), it would benefit many urban customers that do city driving.

I hope HONDA will have a software upgrade to cater the needs of customers.

 

Folks,

I believe we're still mis-understanding where the FE advantages of the HCH-2 come from. Many of us are somehow convinced that the secret to getting great fuel economy is to drive the car in electric. Not so at all.

This is not true for the HCH nor is it true for the Prius... or any other existing high FE hybrid.

The key to great FE is to kick the HCH-2 into its most efficient speed/RPM regimen WHILE minimizing the hits on the battery pack. In other words, keep the battery pack SoC as high as you can. Avoid riding on the electric at all times... unless you can significantly extend your gliding distances to compensate for the extreme SoC loss.

This is true for the HCH-2 as it is true for the Prius.

Steady state driving at the optimal speed range (see Tarabell's article) is where you produce monster FE.
The HCH-2 is already a pretty well balanced system and operates within its intended design profile and because of this, Honda will not release any software updates to increase it electric prowess. Doing so would interfere with many of its design objectives including the life of the battery pack.

Sorry. Such is life.

Cheers;

MSantos

 

msantos,

thanks. I guess I got carried away thinking that I could get batteries charged through regen braking. I fully agree with you that the battery life could be compromised if we drain and re-charge repeatedly.

really learn a lot from you and Tarabell. Thanks again!

Cheers.