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cold air intake??

Discussion in 'Gen 2 Prius Accessories & Modifications' started by AndreJ, May 29, 2007.

  1. AndreJ

    AndreJ New Member

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    Wondering if anyone has installed a cold air intake in there prius and if they know what the results where after the upgrade?>
     
  2. Pinto Girl

    Pinto Girl New Member

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    The air intake hose for the ICE is, if I remember correctly, routed to the RH fender; it's already getting cooler air.

    There's always the electric supercharger!!
    [laughing]
     
  3. Presto

    Presto Has his homepage set to PC

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    Don't forget about the mighty power of the Tornado® Fuel Saver!
     
  4. jewelerdave

    jewelerdave New Member

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    Dont do it!
    changing the manifold to a gap or cold air intake will do little or not good. the prius breaths as much air as a lung cancer patient! it just does not need that much air, it sips gas and works in conjunction with the battery and electric motors.
    The engineers at Toyota set up everything the way it is for a reason and for max efficency.
    There is a reason why a computer controlls the air and fuel mixture so that on every stroke the engine gets exactly as much air and fuel as needed every second at every second that the engine demands it every time.

    The Prius pre warms the fuel going into the engine so it will combust more compleatly so you get max preformance and efficecy already, cooling down the air going into the engine will make the computer dump more fule and run the engine more to keep it warm.

    there have been many posts with people pre heating there engins and insulating them in winter in order to help maintain the heat to keep the engin running at its optimal efficency. And it works for them, Dumping cold air into the engin will counter everything the car is set up to do!
     
  5. Pinto Girl

    Pinto Girl New Member

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    <div class='quotetop'>QUOTE(jewelerdave @ May 30 2007, 06:41 PM) [snapback]452387[/snapback]</div>
    [laughing]
    You're joking...right...? Please answer in the affirmative, even if you're telling an untruth.
     
  6. jewelerdave

    jewelerdave New Member

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    Simple thermodynamics a cold engine does not run as efficiently as one that is set to run at its engineered operating temperature.
    If you take heat away from a system that is trying to maintain a temperature, its going to keep trying to get too that temp. To do this it is going to take energy, that means burning more fuel.
     
  7. Pinto Girl

    Pinto Girl New Member

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    <div class='quotetop'>QUOTE(jewelerdave @ May 30 2007, 06:41 PM) [snapback]452387[/snapback]</div>
    Well, if you want more power, then you need to get more fuel into the engine, and one way to do that is to lower the temperature of the combustion mixture.

    That was the focus of the OP's question, not efficiency.

    ------

    Cooling the temperature of the intake air will *not* cause the computer to " run the engine more to keep it warm." So, I also disagree with you on this point.

    Reciprocating, *air-cooled aircraft engines* do rely (secondarily; they're primarily air and oil cooled) on enrichening the fuel/air mixture to cool the engine. But, as we all know, air cooled engines don't have thermostats to regulate temperature...so every little bit helps.

    Car engines are designed to achieve stable operating temps independent of conditions...this is for emissions compliance.

    You're right about the thermodynamics, I agree. In theory. But you're incorrect in assuming that cooler intake air cools the engine. Especially with a water-cooling, the operating temperature of the engine has so little to do with the density and temperature of the fuel/air charge that, apart from the theoretical, there's no measurable effect.

    Why do you think the Prius doesn't get its intake air from the engine compartment, and instead draws it from inside the RH fender (as opposed to getting it directly off of, say, the exhaust manifold)? As you mentioned, the Prius engineers "got everything exactly right" including making provisions to cool the intake air. Clearly the efficiency question which you raise didn't bother them, did it?
     
  8. hobbit

    hobbit Senior Member

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    The Prius does not preheat intake air unless you help it a little.
    I'm not sure if anyone's bothered with any sort of cold-air mods,
    but plenty of people have fooled around with warm-air intake
    rerouting and this does seem to make a small winter improvement.
    .
    _H*
     
  9. jewelerdave

    jewelerdave New Member

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    So the laws of thermodynamics work for the rest of the world and everyone else but not for Prii and not for people in San Fransisco. Or Just not for Pinto Girl? Or are you trying to argue with me for the sake of argument.
    Or do you really believe this?
    Of course this is the same person that though there would be a housing shortage if the troops came back from Iraq too so I am not surprised.

    Sorry it does not matter who you are, if you add something cold to something hot it will change the temperature.

    Please do some research on the following and how they work.

    Wind Chill factors
    Principals of how a radiator works and why, also how air conditioners work and what happens when you restrict air flow.

    Do a simple experiment.
    Breath on your hand with your mouth open. it will be warm air.
    now, close your lips and blow on your hand with the same power of breath though a tiny hole, it will be cold air!
    thats your air intake, pulling air though a small spot cools the air, now your mixing fuel with that cold air.

    Same reason why a breeze is nice and cool on a warm summer day.

    I have played with cold air intake. I put an aluminum air gap intake on a 350 with an 850CFM carb and yes at idle it had frost forming on the carb because that much air was running though the engine. It was so cold it was too cold to effectively restart the car running ethanol until the heat of the engine warmed it back up when shut off. This is also in high altitude where the air is thinner.
    I had to go back to the cast iron intake in order to keep the top end from getting too cold and to keep the fuel from having issues. Once it went back it did fine.

    Fact is. Cold air intake systems work. And thermodynamics dont change just because you want them to to make an argument.
     
  10. AndreJ

    AndreJ New Member

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    <div class='quotetop'>QUOTE(jewelerdave @ May 30 2007, 07:41 PM) [snapback]452387[/snapback]</div>
    Thanks much for the explanation :D . I have been speaking with someone about modifications of the prius and have now been geared to stay away from the route simply because the computer does so much of the work and for some reason i never put that into the equation. If i did add a cold air intake system a modification of the computer would be needed, which of course could not be done and is slight much just for performance sake. Looks like my next mod will be an engine block heater then.

    Forgive me if this is a dumb question, but a block heater in the summer, is that necessary or can i just turn it off or something, or is there specific temperature that your supposed to run it at?
     
  11. jewelerdave

    jewelerdave New Member

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    Do a search on the block heaters and engine insulation and you will find a lot on the subject. Its going pretty far but if you have it plugged in and warm the engine does not need to do as much as a warm up as you have added that heat. So instead of the first 5 min getting only 25 to 35mpg you get in the 50's or more in most cases I have read about.
    Serious hyper miles seem to like them so with careful driving they can get 700 mile takes.
    Of course its quite helpful in the wintertime.

    Good luck with your endeavors
     
  12. sparkstack

    sparkstack Car Addict.

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    <div class='quotetop'>QUOTE(jewelerdave @ May 31 2007, 12:10 PM) [snapback]452634[/snapback]</div>
    Wow. That's Funny.

    The OP and for that matter "Pinto Girl" are not talking about thermodynamics, they are talking about the rather simple fact that cold air is more dense than warm air. Hence you can get more air in the combustion chamber, and therefore more fuel which combined will make more power. Not that this applies much to the Prius.

    Rather than ranting, i suggest you consult a dictionary. The OP's post and Pinto Girl's reply has more to do with Fluid dynamics than thermodynamics.

    Quite how you made the leap from radiatiors / ac units to internal combustion is beyond me at this point.
     
  13. MickeyA

    MickeyA New Member

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    <div class='quotetop'>QUOTE(sparkstack @ Jun 1 2007, 12:16 AM) [snapback]453049[/snapback]</div>
    Which 1 of these is what you are referencing to in this discipline?
     
  14. Duffer

    Duffer Member

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    Actually this has more to do with crap dynamics, don't put crap on your car, that your car does not need. Modifying the intake system of a car that is already optimized to run efficently, will do far more to lighten your pocketbook, then to give any performance gain. Go on a diet and lose 10lbs. The performance gain from losing 10lbs will be felt in many ways! :D
     
  15. sparkstack

    sparkstack Car Addict.

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    <div class='quotetop'>QUOTE(MickeyA @ May 31 2007, 11:30 PM) [snapback]453053[/snapback]</div>
    Either steady vs unsteady flow or Laminar vs turbulent flow would apply to an intake pipe, but the point I was making is that an engine will make more power breathing colder air. The reason I mentioned Fluid Dynamics as a counter point to "jewelerdave's" Thermodynamics is that velocity, pressure, density, and temperature are the basis of fluid dynamics calculations. All of which are properties that are affected when using cold air intakes.

    Thermodynamics has nothing to do with it.


    <div class='quotetop'>QUOTE(clearview22 @ Jun 1 2007, 06:42 AM) [snapback]453128[/snapback]</div>
    I agree entirely. While an cold air intake "may" increase the power, doing so will decrease the MPG.
     
  16. F8L

    F8L Protecting Habitat & AG Lands

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    Pinto Girl and sparkstack had it essentially right. Cooler air is onviously more oxygen dense and will increase HP if the proper amount of fuel is added by the computer system after being detected by the IAT sensor (Intake Air Temp). It is all pretty basic and well documented on dyno's and racetracks across the country. This is why the best days to race for new times is durring the falls and late winter when the density altitute is at it's lowest. IE, low temps, low humidity, etc.

    After all this tech stuff is said and done, I don't think it makes a big enough difference to be worth it (the Prius doesn't require much air). I tried drag racing my Prius with and without the air filter cover on and I couldn't measure a real difference. Next time I race the car I'll try to be more scientific about the test but for now I wouldn't waste my money on fabing one up. You best bet is to install a good clean air filter and keep it maintained.
     
  17. sting30380

    sting30380 New Member

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    my name is Sean and I'm a new Prius owner. What is "ICE" stand for? And I've also considered replacing my OEM air box and filter to an "Injen short ram-air intake system(model# SP2090)". I was told it will help to gain about 5-10 hp. But do you think it might cause a problem to the "Mass Air Flow Sensor" or the ECU? If you know the answer please advise, thank...
     
  18. F8L

    F8L Protecting Habitat & AG Lands

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    The problem is they don't tell you where that 5-10 hp is at in the rpm curve nor do they guarantee a gain in power. Most CAI systems on tiny engines only produce a gain at high rpm and usually the increase is seen as a peak and not spread out enough to be of much help. On turbocharged or built engines they can be useful but on small stock engines there is not much gain and I guarantee you won't feel the difference. It's all in your head. I sold parts like this for nearly a decade and spent nearly 2 decades racing and testing.
     
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  19. Turtles

    Turtles New Member

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    ICE is short for Internal Combustion Engine, but maybe you were talking about something else?
     
  20. fuzzy1

    fuzzy1 Senior Member

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    He's been gone from PriusChat almost 9 years.