Efficiency sweet spot ?

[shar1950]

If the prius's engine efficiency sweet spot is between 1700--- 2300 rpm When driving around town,doing around 60-70klm/h it is not possible to stay in that range,I'm allway alot lower. How do you people stay in that range ?

[efusco]

<div class='quotetop'>QUOTE(shar1950 @ Apr 29 2007, 04:29 PM) [snapback]432192[/snapback]</div>

If the prius's engine efficiency sweet spot is between 1700--- 2300 rpm When driving around town,doing around 60-70klm/h it is not possible to stay in that range,I'm allway alot lower. How do you people stay in that range ? [/b]

The secret is pulsing and gliding.



Pulse up to or a little above the average speed you wish to maintain within the 'sweet spot' rpm band. Then drop into a glide down to whatever speed you're comfortable going down to. Then repeat. Obviously there are times you simply can't do this (heavy bumper to bumper traffic), but on various other less heavily trafficed roadways it's very much doable.



I may P&G b/w 39mph and 33mph in a 35mph speed limit area...it doesn't seem like much, but I can often glide a solid 1/4 mile or more on a flat area. I expand or contract the speed range for my P&G depending upon the traffic density and route.

[bwilson4web]

<div class='quotetop'>QUOTE(shar1950 @ Apr 29 2007, 04:29 PM) [snapback]432192[/snapback]</div>

If the prius's engine efficiency sweet spot is between 1700--- 2300 rpm When driving around town,doing around 60-70klm/h it is not possible to stay in that range,I'm allway alot lower. How do you people stay in that range ?
[/b]

Lower is OK because you're typically running a much lower power demand. However, something great happens below 42 mph.

I typically cruise around town at 38 mph, 60 k/hr, or less. This allows the car to cycle between ICE on and off and really improves the performance. The key is to avoid 42 mph, 67 k/hr, the transition speed. This can force unnecessary ICE transitions.

Bob Wilson

[efusco]

<div class='quotetop'>QUOTE(bwilson4web @ Apr 29 2007, 10:22 PM) [snapback]432348[/snapback]</div>

Lower is OK because you're typically running a much lower power demand. However, something great happens below 42 mph.

I typically cruise around town at 38 mph, 60 k/hr, or less. This allows the car to cycle between ICE on and off and really improves the performance. The key is to avoid 42 mph, 67 k/hr, the transition speed. This can force unnecessary ICE transitions.

Bob Wilson [/b]

Absolutely agree...I go out of my way to stay at or below 40mph...41 is 'iffy' b/c sometimes the ICE kicks on at 41 and sometimes not....so 40 is my top speed when possible to allow for maximum ICE shut-down when not needed....