Punch it up the slope!

[Jus-A-CMax]

Hmmmh....to get home, I have to climb a gradient which starts literally at the STOP sign.

 

Normally, I would start in EV, then at 15mph kick in the ICE and then let it run on ICE up the gradient which is around 20 seconds. It would drop the MPG by about 0.5 with the ICE on all the time. Battery level is just under 1/2 usually.

 

The last 2 runs back home, I did something slightly different - I start in EV from the stop sign and then I would just "punch" the ICE up in like a giant pulse (not quite yellow lining it) but for about a second or 2 maximum. Then foot off, let it glide/EV a wee bit from the momentum and then punch it again.

 

The thinking is that you lurch the car forward, kick in EV for a little while, and lurch it again and somehow, when you demand power from the CMax _ I am thinking _ it draws and utilizes the EV engine as well. The trick seems to be not to let the ICE part burn long - just build the upward momentum. 

 

Now, I am finding that rather than dropping 0.5MPGs with a continuous ICE, I am dropping say 0.1/0.2 for about 3 pulse and glide up this hill. Saving gas - it seems like it.

 

It sounds really counter intuitive since the engine roars on and then I let it glide and roar again.

 

Anyway, thats me playing to see where i can save some gas. Its not much but every lil bit counts. Next time you're going up a lil hill, try that and see if it works for you. Not sure if this would work on a super steep. I estimate mine is around a 25-30* slope. 

 

 

Be Interested to see if other CMax drivers can replicate this, or improve on this or maybe it's just my lil gradient but I thought I would put this out there for others to play and consider  :rockon: 

 

 

 

[wamba2000]

Other than my wife who has not driven my C=Max yet and is not interested in how your dirve a hybrid for best mpg complaining when I let off ICE to get into EV mode once to speed, I think this pulse/glide method could work.

 

I expect in the next couple weeks to be taking a trip which will involve a lot of hilly country driving.  Will try this an see what my anecdotal evidence returns.

[dtorres]

While this technique seems like it has potential for going up a steep incline I worry a bit about how abusive it is on the engine's components to keep "punching" it as you go up the hill.  Especially if it's a large grade and you have to do it several times in a row before you reach the top.

[plus 3 golfer]

Pulse "punch" and glide works whether going uphill, downhill or on level.  You just have less distance to "glide" going uphill.  

 

Remember the principle of efficient pulse and glide requires a vehicle that will free wheel (engine disconnects from the transmission and shuts down).  So, you pulse to a range of efficient rpm on the BSFC, then glide (engine rpm = 0) rather than maintaining a constant speed and likely less than optimal area of the BSFC while also removing engine rotational losses during the glide.  

 

The addition of a hybrid system can amplify the pulse and glide benefits by storing energy during the pulse phase when the engine is operating efficiently for use later.

 

So the bottom line is to find what combinations of operations maximizes FE for varied driving conditions.  For me it's just a pain to try such continually while driving especially in traffic. :)

[Jus-A-CMax]

I should say, like any other hybrid driving technique, don't try this when there is a car behind you especially if it is a single lane. But if theres no one, hey...

[Jus-A-CMax]

Aha,...I threw it into the Engage mode and did the same thing. Here's whats happening....Max will gun the elec and you can see the blue rise and then it will kick in the ICE. The idea is that you punch elec out, get the car moving and kick in the ICE to move it a little more but just enough for a spurt to get the momentum up the hill and kill it.

 

Also, you need about 1/2 battery for this so that the elec has some juice. So throw the left view into Engage mode and watch it work.

 

 

IMO, this is ideal for short spurts, low to no speed up hill runs - a problem I have sometimes as I drive around the houses. As versus more time on the gas pedal for ICE to burn constantly.