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New Prius C owner. Several Questions

Discussion in 'Prius c Main Forum' started by Need4Camaro, May 7, 2020.

  1. Need4Camaro

    Need4Camaro Junior Member

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    Hello.

    I purchased a 2015 Prius C for a daily driver and it's a cool car around town. On the highway admittedly it's kind of dangerous out here. We have 75 - 85 MPH speed limits where I live and often times people are driving faster than that and quick acceleration is a must in some areas here, both of which the Prius C strongly lacks. I do love the fuel mileage though.

    I have a few questions.

    What kind of fuel mileage should I be getting while cruising at 70 MPH? I am barely able to get 33 - 35 MPG at that speed. Now on the street and city driving I average between 42 - 45 MPG.

    Is there anything I can do, regardless of how extensive, to improve the acceleration of this car without ruining its fuel mileage? I would like power in reserve so to speak just incase I need to accelerate quickly.
     
  2. Pri3C

    Pri3C Active Member

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    Welcome :) I’m a newer Prius c owner as well and have driven a couple thousand highway miles. My highway mpg is usually between 45-55, with 48-50 being the average so far. My local roads are relatively flat. Extreme temps and high winds can have a negative impact on mpg. If the Prius is driving in the same direction of a strong wind it will help to propel it forward. I also think it’s designed to work with the wind coming straight at it, but those crosswinds will get ya! In town I get anywhere from 45-70.
     
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Our long term average is around 49mpg.

    The fuel economy for these cars, well for any car, goes off a cliff above 65. We drive ours on the same roads as everyone else, sometimes at 70-80mph. When we do that, the instantaneous gas mileage drops fast. But sometimes we need to go that fast and so we put up with it.

    Your reported numbers sound low, but only a little. You might verify that the tire pressure is high enough and perhaps review your aerodynamics- does this car have a roof rack or any other optional accessory hanging out in the breeze? Factory wheels and original tire size?

    There really isn't much you can do to gain acceleration in these, especially in the 50-70 range, assuming that yours is running correctly.

    I got curious once and ran the numbers. The c can accelerate faster than my old VW vans and my Ford Ranger truck, but it's slower than just about any other car I've owned. It's loads faster than any semi truck and they're out on the same roads I am.

    It can take a little getting used to, but I've never found a traffic problem I couldn't conquer in this car. But if you really do need that surplus power I'd suggest getting something else and burning some more fuel on purpose.
     
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  4. sam spade 2

    sam spade 2 Senior Member

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    Two things will kill the max. mileage you can get with a hybrid:
    High speeds and hard acceleration.
    Long stints of stop and go grid lock rush hour.

    It sounds like you have a lot of both.....given the mileage numbers you quoted.
    The PC might not have been a good choice for your "normal" driving conditions.

    We have been able to average close to 50 MPG....BUT it seldom gets above 55 MPH.

    And there is only ONE thing you can do to get more performance:
    Trade it in. Seriously.
     
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  5. AlphaFox

    AlphaFox New Member

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    Get an intake and exhaust for more power. about 10% more.
     
  6. sam spade 2

    sam spade 2 Senior Member

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    Except for a "placebo effect" increase, more power is iffy.

    But worse fuel mileage is pretty much guaranteed.
    And you will have that terrible "go cart" sound too.

    Actually I think most go carts sound better.
     
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  7. davidc83

    davidc83 Member

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    Really nothing you can improve the acceleraton...it has a 1500 cc motor, has less than 100 hp (less than 90 in eco mode), weighs close to a ton with driver...if i keep the car less than 65mph, i get approx 55mpg...70mph around 48 mpg and 77 mph,,,, get around 41mpg and over 80mph, get mileage in the upper 30 mph...sounds like your car is normal..

    SM-S367VL ?
     
  8. Montgomery

    Montgomery Senior Member

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    Mr. SamSpade, do we go into detail with davidc83 about the AtchinsonCycle motor and its timing cam difference over regular cycle motors?
     
  9. sam spade 2

    sam spade 2 Senior Member

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    No. "We" will do no such thing.
    And I think that if YOU somehow feel obliged to do that, it will just be a waste of your time.
    I think he gave a perfectly good summary of the situation.
     
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  10. Need4Camaro

    Need4Camaro Junior Member

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    Just dead curious what would happen if one were to swap the 1.8L in from the Prius Standard?
     
  11. The Electric Me

    The Electric Me Go Speed Go!

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    I don't know.
    When a Poster comes to Prius Chat with a moniker of Need4Camaro, and his first salvo of questions about his Prius c, are all about how can he improve horsepower and acceleration, followed by what if I swapped in a bigger engine?, I'm really tempted to say...WRONG car for you.
    The Prius c, is not about quicker acceleration or swapping engines.
    It's about Hybrid Synergy Drive and all the components working together to return cleaner emissions and hybrid fuel mileage. It's all been engineered to work together.
    No project is impossible, but basically the computer, the engine, the electric motors, the transmission, the regenerative brakes, the whole system has been designed to work together. IMO this isn't a get it in the garage and put a totally different engine in it type of ownership experience.

    If you're not going to be happy with that reality? I'm saying ditch the Prius c, buy yourself a daily driver 2nd Camaro.
     
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  12. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    It's more power, but it might not go well. One of the fundamental things to understand about the Prius is balance. The power split device requires, mechanically speaking, a certain amount of harmony between the gas engine and the two motor-generators. A lot of time went into harmonizing these for each of the various iterations of the Toyota hybrid synergy drive with different engine sizes, electric motor ratings, and battery capacities. The results of that were baked into the program code for the various onboard computers.

    You go changing one electromechanical element without changing the others, you invite trouble. Maybe not real actual trouble, but enough to confuse 6 ECUs on the car and throw error codes. Ok maybe that is real trouble; depends on your tolerance for weird car behavior.
     
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  13. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Neither will have an effect on an Atkinson cycle engine's power. This simply make noise.

    The Atkinson Cycle engine spews as much as 30% of the air already back into the intake manifold, so it is never a 'Cold Air Intake'. Shorting the intake will change the Air/Fuel mixture and throw codes, as you are not running the right ratio.

    In an Otto Cycle engine the exhaust is still expanding in the exhaust system, so larger is 'better' With the Atkinson Cycle engine exhaust pressure is already atmospheric, so a larger exhaust does not help.

    For more performance, lower weight. Buying lower weight parts will almost never pay for itself, just make sure you are not carrying stuff you aren't using, like mothers in law.

    If money is no object, forge wheels will improve handling and economy, but are typically over $1000 per wheel.
     
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  14. Need4Camaro

    Need4Camaro Junior Member

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    I get what you mean. I actually like my Prius it's fantastic on the street it's just alittle unsafe here on the highway because how fast people drive where I am and I cant really make emergency moves with it.

    How is the Prius Standard as far as driving on the highway? Any other hybrid models that have decent acceleration on the highway? It doesnt need to be a Camaro it just needs to beable to move accelerate decently in the event an emergency happens and I need to get out the way.
     
  15. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Basically all of the others. You more or less found the only one that works great on city streets but runs out of breath on the freeway. This is especially true in the most recent model years.
     
  16. The Electric Me

    The Electric Me Go Speed Go!

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    I owned Gen 3 Prius standard.
    But I just kind of have repeat the same Mantra.
    IMO...My Prius accelerated "safely"...I could use the power mode, if the merge on the freeway was particularly crowded, but basically I felt the Prius capable of accelerating safely.
    But the 0-60 times of a Prius, are never going to impress those that even care about 0-60 times.
    The Prius is an Atkinson cycle engine, employed for better fuel efficiency, not quicker response times. I felt my Prius easily capable of reaching and maintaining any legal cruising speed on the freeway, in fact it remains to me the best road trip vehicle I ever owned.

    But IMO owning and operating a Prius shouldn't ever be about speed. You have to be valuing the Hybrid benefits when you own and operate a Prius.
    You aren't the first person to come to Prius Chat and say they felt unsafe with the acceleration capabilities or freeway mannerisms of the Prius. But again? The advice is the same.
    I'm NOT being sarcastic, it's sincere advice. I would say to anyone, with any vehicle, if you don't feel safe driving it in the environment you often drive it in? Then it may not be the vehicle for you.

    Also, I think with each succeeding Generation Toyota has advanced and the "compromise" gap of Hybrid performance vs. ICE performance has lessened. In some of the early Gen 4 Prius advertising the Gen 4 is presented with sports car like imagery. Spinning tires on rain soaked streets..etc...

    But for now? The Prius is the Prius. And it's purpose built for efficiency, not acceleration or speed. Maybe that is changing, if you compare Gen 1, Gen 2, Gen 3, Gen 4...
    The sedan Gen 1 Prius actually has a dash board icon of a turtle on it. So we've come a ways.
    But I still say, if you're driving a Hybrid, you have to want the primary benefits of a Hybrid. And those are efficiency, cleaner emissions, not muscle car or sports car attributes.

    You might find a little difference/.comfort between the Prius c and a Standard Gen 3 Prius. The Gen 3 Prius does have a "power mode" button, which basically remaps the response time in pressing the accelerator pedal. But I think the general advice holds true...for all Prius.
     
  17. AlphaFox

    AlphaFox New Member

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    Unless you completely floor it the sound is not much different.
    And Injen has a dyno result that shows 7HP just from the intake, no placebo required.
     
  18. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    If they convince you that that Dyno is real, they hope to get your money. Never trust the vendor.
     
  19. AlphaFox

    AlphaFox New Member

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    eh whatever. seems faster to me.
     
  20. MSAGRO

    MSAGRO 2010 Prius Five with Advanced Technology Package

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    C stands for “City”

    Not American interstate highways.

    you can safely drive on them in the Prius C, but it will not evoke confidence like an American V8.

    As far as freeway speeds are concerned, 0 to 20 miles an hour is an absolute embarrassment, but going from 20 miles an hour to 60 miles an hour is actually pretty smooth and better than what you would imagine.