To Cruise Control or not to Cruise Control

Discussion in 'Prius c Fuel Economy' started by iBO, Mar 24, 2015.

  1. iBO

    iBO New Member

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    On the I495 capital beltway around DC and on I270 in Montgomery country.. speed limit is 55 and there are 4 lanes.. I was driving on the 3rd lane from the left and was not bothering anyone. In fact I had to move to the second lane few times to drive pass big trucks and 18-wheelers.
     
  2. Dimitrij

    Dimitrij Active Member

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    ^ I was wondering if my ECO thingy inaccuracy is my specific problem, or is it a common phenomenon.
     
  3. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    I drive a G3, but back when I was in my hypermiling kick, I used to beat the CC for tank efficiency every time, everywhere.

    However (comma!) 600 miles of continuous hypermiling isn't worth the additional few tank MPG that I get from my herculean efforts.....so I pretty much use the CC, especially when I'm on the interstate.

    For the last 80,000 miles I've saved enough by driving a fuel efficient car to forgive myself the sloth of letting the car maintain a more consistent speed, which is probably more considerate for the people that I have to share the roads with.

    Your call.

    Good Luck!
     
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  4. Easy Rider 2

    Easy Rider 2 Senior Member

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    Either way the DIFFERENCE should show up almost exaclty the same.
    The onboard "gauges" can be very useful to see relative changes in MPG but just can't be trusted for absolute values.
     
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  5. frodoz737

    frodoz737 Top Wrench

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    Yep...what he said.
     
  6. Sean Nelson

    Sean Nelson Active Member

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    The secret is to find a truck doing 60 and just follow along at a safe distance behind it. People may think you're stupid for not passing but they'll blame the truck for slowing them down, not you.
     
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  7. frodoz737

    frodoz737 Top Wrench

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    Yea, but on "my" exampled trip, the trucks were the ones most upset...and rightly so. Know one should impede traffic like that.
     
  8. ufourya

    ufourya We the People

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    You can have a little fun with your commute. Taking into account that your trip to, and the return, might represent significant elevation changes, you should do your calculations for the whole enchilada - to and fro.

    By my rough calculation, the difference between 75 MPH and 55 MPH for 40 miles is about 12 minutes. So the difference between driving your commute at 75 and at 55 would be about 24 minutes a day. By calculating the MPG for each variation in the relationship, you can figure out how much those 24 minutes are worth to you in dollars and cents.

    Let us know. :)
     
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  9. iBO

    iBO New Member

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    So far, very happy with fuel efficiency. I have filled the tank 3 times so far and each time I got about 450 miles driving regularly, although in the 60s rather than in the 70s like I used to.
     
  10. bisco

    bisco cookie crumbler

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    see, the prius returns you to sanity.:p
     
  11. Dimitrij

    Dimitrij Active Member

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    I wonder if Prius should have a cruise control whose algorithms (at least in ECO mode) is more sensitive to the fuel savings paradigm. From what see, the cruise control operates in a traditional way: it forces the car to attain the set speed no matter what, and within a relatively short period of time.
     
  12. Easy Rider 2

    Easy Rider 2 Senior Member

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    NO. That would result in allowing it to deviate from the set speed even more than it does now.
    I don't think that would be a good thing........for traffic flow in general.
    Safety first; efficiency second.
     
  13. Dimitrij

    Dimitrij Active Member

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    That's certainly true, but isn't what (some) Priusites do anyway while hypermiling? On some of my daily routes there are a few 55 mph uphill stretches that 'c' can't even keep 45 mph. That said, I have stopped using the 'c' for these trips.
     
  14. Easy Rider 2

    Easy Rider 2 Senior Member

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    Yes and I think that is a BAD idea too.......if there is other traffic around.
     
  15. Dimitrij

    Dimitrij Active Member

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    Apart from safety (#1 no doubt), there is also the law of diminishing returns and the value of your time: improving from 45 mpg to 50 mpg doesn't save too much money at all. In my case, I do about 40K miles/year, spending let's say 1,000 hours on the road. With hypermiling, this time is likely to increase by 5% or 50 hours and reduce my gas usage by 90 gallons a year (50 mpg vs. 45). Even if gas is $4.00/gallon, that would save $350.00 or thereabouts, but you'd spend more than a working week (!) in traffic.
     
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  16. Brad K

    Brad K Member

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    CC is great on flat terrain. But hills CC will suck up gas compared to my manual style of slowing up hills and speeding down them. I get alot better mpgs than maintaining the same speed up and down hills
     
  17. Easy Rider 2

    Easy Rider 2 Senior Member

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    Well you won't be quite so proud of those extra "mpgs" when somebody rear-ends you because they don't notice your erratic speed changes.
    :(
     
  18. fuzzy1

    fuzzy1 Senior Member

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    Normal hypermiling doesn't involve rapid enough speed changes to cause unimpaired drivers to rear-end anybody.

    The impaired drivers (intoxicated, distracted, or fatigued) are a serious hazard to everyone, speed changes or not. It is imperative that they be removed from the road promptly.
     
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  19. Dimitrij

    Dimitrij Active Member

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    Quite so. I believe erratic and/or uncivilized drivers represent a much higher risk to themselves and others than a reasonable hypermiler, or, for that matter, someone who is going X mph above the speed limit but is considerate enough not to tailgate or to change lanes w/o signaling.
     
  20. Brad K

    Brad K Member

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    I wouldnt say Im driving erratic at all
     
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