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Discussion Starter · #1 ·
I've been playing with my OBD2 ScanGauge, it appears if the cruise is set to 49 mph then hybrid system will not spin the ICE when coasting, if speed is approx above 50 mph it will maintain about 1000rpm. This appears to give great mileage. 49 is still around the legal limit in my area.

I've got really great mileage playing with this, the battery monitor charged fast and went quickly up to 9/10 bars. I've only seen 9 bars on long descents in mountains before.

Was able to beat my commute record of US 50 MPG by a solid 56 US MPG this the only changed factor.

Can anyone confirm the theory behind this?

( btw claimed official mixed driving figures are 47 MPG in this market )
 

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All the hybrid systems have a speed at which the ICE MUST run in order to lower the RPM of the MG. Above that speed there's no true EV mode available. Whether it makes any difference to MPG if the ICE is running or not is an open question. If your power meter is in the ECO zone it makes little or no difference if the ICE is running or not. (at any speed) Its also true that in some circumstances the ICE gets no fuel even if it is turning, usually in the 47-68 mph range.

The speed varies from model to model depending on the final drive ratios and which generation of hybrid drive is in use. In the US Rav4 models that speed is close to 47mph.
 

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Discussion Starter · #3 ·
Thank you for the explanation rdgrimes!

I would imagine that spinning things are not for free, even if there are no fuel consumed. I'm thinking about pump/friction losses in the ICE and that there is some type of clutch between ICE that is robbing power.

Case a:
*ACC 51 MPH, slight downhill. ACC starts dipping into CHARGE area and spins the ICE (with no fuel used)
=> Gravity pull - spin_losses - charge = less amps going into the traction battery

Case b:
*ACC 49 MPH, slight downhill. ACC starts dipping into CHARGE area.
=> Gravity pull - spin_losses - charge = more amps going into the traction battery

Just my simple theory :)
 

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I've been playing with my OBD2 ScanGauge, it appears if the cruise is set to 49 mph then hybrid system will not spin the ICE when coasting, if speed is approx above 50 mph it will maintain about 1000rpm. This appears to give great mileage. 49 is still around the legal limit in my area.

I've got really great mileage playing with this, the battery monitor charged fast and went quickly up to 9/10 bars. I've only seen 9 bars on long descents in mountains before.

Was able to beat my commute record of US 50 MPG by a solid 56 US MPG this the only changed factor.

Can anyone confirm the theory behind this?

( btw claimed official mixed driving figures are 47 MPG in this market )
I can't confirm any theories because I did not get in depth into this, but I can say that on my daily commute when the conditions are slowed because of traffic that I can go for long periods around 45 MPH where I am coasting. I usually go from lower 30's MPG for the first half of my commute to almost 40 MPG for the other half. All of this is great in that we are finding ways to maximize efficiency and I think Toyota did a great job with this system to the point that we can get even more out of it than it is supposed to give.:smile
 

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Discussion Starter · #5 ·
I can't confirm any theories because I did not get in depth into this, but I can say that on my daily commute when the conditions are slowed because of traffic that I can go for long periods around 45 MPH where I am coasting. I usually go from lower 30's MPG for the first half of my commute to almost 40 MPG for the other half. All of this is great in that we are finding ways to maximize efficiency and I think Toyota did a great job with this system to the point that we can get even more out of it than it is supposed to give.:smile
Yes! Love this forum with all the great knowledge sharing and friendly atmosphere.
I checked your fuelly account now. Nice car you have there.
 

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I can confirm it works to a degree. I did 20 kms at around that speed earlier this week and with light pulsing and gliding, I was about to squeeze out 52 MPG or 4.5L / 100 km on the mileage indicator.
 

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49mph sounds about right as the air resistance "sweet spot" for the RAV4 body design

speed^4 = air resistance
 

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Discussion Starter · #8 ·


Todays commute 40km / 25 miles



Entire tank hoping to get atleast 600 miles, my dream is 1000km (621 miles)

At 49/79 it is able to go on pure electric in low load conditions, not only coasting benefits, well thats my theory.
 

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Discussion Starter · #9 ·
49mph sounds about right as the air resistance "sweet spot" for the RAV4 body design

speed^4 = air resistance
I think you are right.

49 seems like the sweet spot, its still reasonably fast to travel at 49, 55 is also very good. 51-54 seems abit pointless according to my observations.
 

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Anecdotally, I've noticed that when I'm on secondary roads doing 40-50 mph, I get really really good mileage. High 30s low 40s. But on the highway, I like to drive 80, and that puts me back around 35 on a tank (warm) or low 30s in colder weather.
 

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Discussion Starter · #11 ·
Anecdotally, I've noticed that when I'm on secondary roads doing 40-50 mph, I get really really good mileage. High 30s low 40s. But on the highway, I like to drive 80, and that puts me back around 35 on a tank (warm) or low 30s in colder weather.


Anything above 65mph kills the mileage :)

Yellow reserve / fuel symbol came on now at 900kms. Who think I can make 1000kms or 600miles / 960kms :)

Usually i can fill 3 gallons when yellow symbol appears :)

 

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That's pretty good for 80 mph. When i was driving across Oklahoma going 77 mph I was getting 27 mpg. I figured driving above 75 was my issue but I also had a moderate headwind too.
 

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Is it possible that the anti-pollution rules are less restrictive in Europe than US/Canada and makes the RAV4H more fuel efficient? I don't see how I could do 5L/100 km! The only way I could achieve this is driving almost exclusively in city with a lot of 50 km/h or less!!!

4.8L/100km is very impressive!
 
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