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Discussion Starter · #1 ·
The other day, it was snowing and the gi'f and I took a drive up a canyon road. Conditions were not the best, so I had to keep the speed down. Two things:
  • Driving uphill, maintaining like 30-35mph, the battery eventually stopped assisting (obviously, since I was never charging it). The car has NO POWER without the IMA at low rpm.
  • Coming back down I, naturally, kicked the car into a lower gear (2nd) to maintain a low speed with no braking. All was great while the battery was charging. Once it was charged fully, the IMA kicked off. Suddenly, there was NO bhp to keep the car from rolling faster. I had to use the brakes way more than I liked


What are your guys' thoughts on this? It makes the car .. interesting .. to say the least.

The gas engine really needs a boost (pun intended) ;)
 

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it hasnt gotten bad here yet so i cant comment on driving in bad weather, but i will say that i have NEVER drained the battery. Pittsburgh is hilly but i guess i do a good job of not driving up hills or something....
 

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I drive the truck when it snows, but if I get caught in the Z, I will get back to you. There is a significant hill leaving work.
 

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I am planning on going skiing/boarding this winter, and the CR-Z is now my only vehicle. So I will post how it does. I will have good winter tires, and I have the MT. Colorado has lots of serious grades, when heading to / leaving the ski slopes.. so it will be an interesting time. I don't anticipate any problems though.


Veonik.... do you have a CVT? I have never had an issue with control on long downhills.. that is about the only time ALL battery bars get filled up.

EDIT: re-read your post.. looks like you do have MT. Odd.. I have never had to use brakes downhill to control speed.. just downshift.
 

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Discussion Starter · #5 ·
Yeah I am also looking forward to the boarding season but I'm pretty worried about the lack of power. I did not have actual control problems-- the car is very stable and the stability control works great when traction is lost.

The problem is when I was coming down, after the battery was fully charged, I was trying to keep it at around 20-25mph so I didn't have to brake before corners. The car didn't have enough power (in the gas engine) to keep the speed down in 2nd gear. 1st was revved way too high for comfort so I just eased down the mountain. Again, this only happened when the battery was fully charged and IMA kicked off.


Also, going uphill is alright when you can keep a healthy speed up. I've noticed that if you are driving spiritedly uphill, you still have to brake into corners which charges the battery enough to pull you out of the turn.




Sorry, I suck at explaining things. :D
 

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At speed exceeding 15 mph (that is while vehicle moving not when you start vehicle roll from dead stop)...IMHO you should not put it back into first gear, not to mention slightly difficult due to resistance, unless you slammed it in. If you keep your transmission in gear going down hills, the transmission brake would slow the vehicle down to a manageable speed allowing safe control of your vehicle. If you have to tap on brake, you can do it ever so gently and that would slow vehicle down enough to have better control. Even in automatic trans vehicle, you still have to use your brake to slow descent for safe maneuvering.

I personally don't have the problem you described. Yes, I do go down steep incline day in day out. I almost never use my brake but if I do...I do it ever so gently to slow the descent by a tad allowing me to take the corner safely and I seldomly use the gas pedal to accelerate allowing the incline grade to bring me back to speed.

Now going uphill without IMA... Yes, you do loose some power preventing you from being an aggressive pace setter up the hill but it does have enough spunk to keep up with the best of them at a safe speed. The sudden lose of power is slightly noticeable but not so that it is unsafe. Being on manual transmission you must down shift. I am usually down shifting to 4th gear or if steep enough 3rd or 2nd but rarely unless traffic comes to almost a stop. Now shifting while you going uphill, you will feel your vehicle slow down while shifting but you will be fine. (Some will advise you to power shift in this scenario but I personally preferred not to.) I do pass some slow drivers going uphill when the IMA battery is depleted with little difficulty.

There is a little learning curve to driving a hybrid but overall I think this vehicle has spunk. If you want to truly know what a lose of power is...try going uphill in a Prius with the battery depleted. Happen to me in terrible traffic and had my hybrid battery depleted. Boy was it painful. The Prius was a great vehicle using a different hybrid technology but :eek:fftopic:
 

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Some will advise you to power shift in this scenario but I personally preferred not to.
Power shifting is indeed not proper when downshifting while going uphill (or while overtaking).

Going uphill you often need to downshift if you want to keep your speed constant. However, when you downshift normally, you will as you state slow down because of the engine breaking, which is exactly the opposite of what you want !

In that situation, the proper technique is double declutching. It goes like this :
When you want to downshift, instead of going straight into the slower gear, you put your car in neutral, you release the clutch, you then press briefly the gas pedal in order to increase your engine rpm to the rpm you would have going at your current speed in the lower gear ratio, then declutch and downshift.

With this technique you will have downshifted without causing engine braking and as a bonus your tranny synchro will thank you.

It takes a bit to get used to but it's not so hard. The idea is to be able to do it very quickly (under a second).

A similar effect can also be accomplished without going into neutral : declutch, give some gas and downshift. You also will avoid engine braking but not synchro wear (or so I heard).
 

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Power shifting is indeed not proper when downshifting while going uphill (or while overtaking).

Going uphill you often need to downshift if you want to keep your speed constant. However, when you downshift normally, you will as you state slow down because of the engine breaking, which is exactly the opposite of what you want !

In that situation, the proper technique is double declutching. It goes like this :
When you want to downshift, instead of going straight into the slower gear, you put your car in neutral, you release the clutch, you then press briefly the gas pedal in order to increase your engine rpm to the rpm you would have going at your current speed in the lower gear ratio, then declutch and downshift.

With this technique you will have downshifted without causing engine braking and as a bonus your tranny synchro will thank you.

It takes a bit to get used to but it's not so hard. The idea is to be able to do it very quickly (under a second).

A similar effect can also be accomplished without going into neutral : declutch, give some gas and downshift. You also will avoid engine braking but not synchro wear (or so I heard).
IMO, Matching RPMs is the best way to shift anytime... much smoother, and more natural than double declutching.... do it enough, and you do it without even thinking about it.
 

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Well double declutching and standard rev matching is the same thing and both will have the same exact result as far as the car handling is concerned.

Which one you choose is a matter of preferences. Personally I prefer to double declutch but I only use that technique when downshifting would leave the engine reving high in the lower gear.

Also I am not qualified to explain why but it is said that double declutching prevent synchro wear but single declutching rev matching don’t.
 

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aha - long time ago I used to have to double-de-clutch on trucks with crash gearboxes. Havent done it for ages, so might give this a try sometime.
That said, we've got a really steep hilly bit locally, and if I keep her in 'normal' & shift briskly when going uphill, tho the battery does empty - its never been a problem to keep on the move. It might not be so easy when we have snow, which is forecast for about 2 days time.........

Mind you, my other 'current' car is an 8 yr old smart, so am used to things needing a bit of a boot to get about!:rolleyes:
 

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Very informative suggestions. Thanks lelag and CraZee for more options and clarification. :hi5:
 

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Power shifting is indeed not proper when downshifting while going uphill (or while overtaking).

Going uphill you often need to downshift if you want to keep your speed constant. However, when you downshift normally, you will as you state slow down because of the engine breaking, which is exactly the opposite of what you want !

In that situation, the proper technique is double declutching. It goes like this :
When you want to downshift, instead of going straight into the slower gear, you put your car in neutral, you release the clutch, you then press briefly the gas pedal in order to increase your engine rpm to the rpm you would have going at your current speed in the lower gear ratio, then declutch and downshift.

With this technique you will have downshifted without causing engine braking and as a bonus your tranny synchro will thank you.

It takes a bit to get used to but it's not so hard. The idea is to be able to do it very quickly (under a second).

A similar effect can also be accomplished without going into neutral : declutch, give some gas and downshift. You also will avoid engine braking but not synchro wear (or so I heard).

aha - long time ago I used to have to double-de-clutch on trucks with crash gearboxes. Havent done it for ages, so might give this a try sometime.

I did a little digging around for explanation; purposed of double declutching technique. :p

Unless you are driving a big rig, older trucks or automobiles built before 1920....you do not need to double declutch. It is completely unnecessary with our synchronizers transmission.

Here is a quote from Wiki, "A double clutch (also called a double declutch) is a driving procedure primarily used for vehicles with an unsynchronized manual transmission."

Most newer manual transmission are built with synchronizers transmission introduced in 1920...way before my time. :rotfl: :eek:fftopic:




IMO, Matching RPMs is the best way to shift anytime... much smoother, and more natural than double declutching.... do it enough, and you do it without even thinking about it.
:yeahthat:
 

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Unless you are driving a big rig, older trucks or automobiles built before 1920....you do not need to double declutch. It is completely unnecessary with our synchronizers transmission.
err - in the UK there were plenty of 7.5 tonne 1970's trucks built with crash gear boxes.
The 1st one I drove was a Leyland Redline - that was a 1975 reg & I was driving it in 1984 (goes off to hide for admitting I'm old!)
 

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err - in the UK there were plenty of 7.5 tonne 1970's trucks built with crash gear boxes.
The 1st one I drove was a Leyland Redline - that was a 1975 reg & I was driving it in 1984 (goes off to hide for admitting I'm old!)

:rotfl:

Older trucks are slow to move therefore still uses those crash gear boxes but smaller automobile started using those synchronizers transmission in 1920 per WIKI information. I am not very familiar with this but it provides some interesting reading.

No worry being old as long as you keep thinking young. hahaha. My mouth is saying I am 21 but my body is telling me otherwise. :pP: :giggle:
 
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