Best way to accellerate for ICE efficiency?
 

It's been posted either here or on PriusChat that those with additional instrumentation can see that keeping the ICE rpms above 1500 is key to getting the most efficiency out of it when it is running. Those of us not enjoying instrumentation may not know how to accomplish this.

Going by ear, I can hear how rapid the engine is revving. Starting from 0 I accellerate gradually, the ICE kicks in with a slight high rev then settles to, what sounds to me, to be a very low rev - so I accellerate somewhat sharply, then slowly relax the acceleration as I pass upwards through 30 and 40mph - this makes the rpm sound relatively constant, though again without instruments I don't know.

Those with instruments care to share? Do you do this sharp accel at 15mph, slight accel at 40 pattern?

Re: Best way to accellerate for ICE efficiency?
 

Hi,

With instrumentation, it is easy to 'learn' but difficult to teach. What I'd like to suggest is there are ways to add temporary instrumentation that can easily be removed when going to see Toyota:

http://home.hiwaay.net/~bzwilson/prius/motor.html
http://home.hiwaay.net/~bzwilson/prius/magnetic.html

My initial experiments simply ran the ethernet cable through the hood gap and in through a window, cracked open. It could probably be door closed but that might stress the seals. Regardless, the signal can be recorded by a laptop and analyzed later. Alternatively, 'listen' to it by playing while recording.

Basic stuff.

Have fun!

Bob Wilson

Re: Best way to accellerate for ICE efficiency?
 

Basic stuff to those who don't find walking without tripping challenging ;o)

I am of the other camp. Nothing you can teach someone without instruments?

Re: Best way to accellerate for ICE efficiency?
 

Everybody has a nice instrument called Energy Monitor screen.
You can accellerate briskly unless you see a yellow arrow from battery.
It is not a good idea to use the battery power on accelleratation.

Ken@Japan

Re: Best way to accellerate for ICE efficiency?
 

...Really? But at say 15mph, pressing light enough to avoid seeing a yellow arrow means basically idle rpm from the engine... .

Idle being 1000rpm, below 1500.

Re: Best way to accellerate for ICE efficiency?
 

Ken is right and I am embarressed to not know the 'characteristics' of the MFD display indicators even in my Prius, much less, the thresholds of the NHW20, 04-current Prius. I've seen a number of web pages discussing the MFD but don't remember any that covered the engineering thresholds for the various arrows.

Bob Wilson

Re: Best way to accellerate for ICE efficiency?
 

what i recommend is using the Engine to drive the wheels and at the same time propelling the ELECTRIC Motor in which it will TURN THE WHEELS, the battery in the meantime has nothing to do with the associated action.

here's a picture of what I do on my 03 prius, although I heard that this type of acceleration is easier to achieve on the classic than the current generation prius.

http://img165.imageshack.us/img165/6...emotordmz4.jpg

This ensures you get the most acceleration of what the engine has to work for. Instead of sending some back to the battery (conversion losses) however when your in this state http://img176.imageshack.us/img176/8...edrivecuw6.jpg

your usually climbing speed very slowly however, your current mpg should be pretty high (>40 mpg)

Re: Best way to accellerate for ICE efficiency?
 

Hmmmm so generally, keep the battery out of the equasion as much as possible? That kinda makes sense.

Ken I initially thought you meant the yellow arrow from the motor to the wheels but now I see that you mean only from the battery to the motor, which makes more sense. I'll have to play with accellerating near 25mph to see what the thresholds are for keeping arrows in either direction from appearing there... .

Re: Best way to accellerate for ICE efficiency?
 

Following is a Bible of P&G...
http://hybridcars.about.com/od/owner...seandglide.htm

Ken@Japan

Re: Best way to accellerate for ICE efficiency?
 

Mmmm... sadly there's not much more there about the "Pulse" part than preventing the battery arrow. That's the trick I suppose - literature about Pulse and Glide tends to focus on the Glide.

Oh if only the Prius dash came looking like this:
http://www.cleanmpg.com/photos/data/...ge_Cluster.jpg

Is the basic reasoning for accellerating without the battery that, in order to get that energy to the wheels it had to be gas burned > momentum > electric > momentum? The energy you're using is the most conversion-costly?

If so it seems like you'd basically want to accellerate as hard as possible without that showing, so the engine revs in the 1800-2400 ideal range, while the battery is untouched.