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"Stealth" at speeds above 42mph

Discussion in 'Gen 2 Prius Main Forum' started by TucsonPrius, Jul 9, 2004.

  1. john1701a

    john1701a Prius Guru

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    Well that's rather primitive.

    How about if it sends the data as a spreadsheet through a bluetooth connection to your cell-phone or PDA?
     
  2. Frank Hudon

    Frank Hudon Senior Member

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    ok make mine USB as I wouldn't want someone beside me at an intersection with his PDA having a look at my data or sending me a virus. I can imagine a virus that makes the car miss at say 41 44 miles per hour, the dealer would probably never figure something like that out.
     
  3. Jonnycat26

    Jonnycat26 New Member

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    If you're talking about using the BT connection in package 9 systems, it's not possible.

    It's pretty firmly tied into the telephone portion of the nav package, and as far as getting it to do much other than the butchering of vCards it likes to do, I don't think it'd be very easy to do. You'd have to modify the firmware of the car, and that's not something I'd think many people would do lightly.

    As an alternative, why not just go out and pick up a discontinued palm with the universal connector and use that as your display? It's easy enough to hack the universal connector into a serial connection....
     
  4. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    For the poster who stated that the valves are held open, this is not possible since the cams still spin during engine freewheeling. What is possible though is that the intake cam timing can be modified via VVT-i to minimize pumping losses during this "free spin" mode. This minimizes drag at speeds above 42mph if no engine power is requested - unless you're coasting where this could be desirable if regeneration drag alone is insufficent.
     
  5. Frank Hudon

    Frank Hudon Senior Member

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    an internal combustion engine only requires about 2 1/2 hp to start it so very little energy from the CVT is needed to spin the ICE and no the valves are never held open as Rick pointed out. The VVTi retards the intake cam to lower pumping pressure.
     
  6. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

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    well there is a principle of momentum and its the same principle that says to maintain a speed of 65 mph, an average car expends about 23 HP to do so. Because of the lower than average wind drag coefficient, that figure would be lower for the Prius. so you see, from a running start, not much is needed to maintain speed. that is the beauty of the atkinson cycle engine.
     
  7. victor

    victor New Member

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    Fair enough. As I said I am no expert but I got this impression from this
    from Johns site http://john1701a.com/prius/prius-misconceptions.htm about 1/2 way down the page. (Bold is mine)
     
  8. Tempus

    Tempus Senior Member

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    I didn't think all the Valves were all held open all the way through each cycle. I thought the Timings were adjusted so that the Intake and Exhaust Valve openings Overlapped - IE, there is always at least one valve open.

    This means SOME pumping loss, but far less than if both valves were closed at the same time at a point in the cycle.
     
  9. ceemom

    ceemom New Member

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    Neutral to Drive

    Just wondering about coasting. Can you shift from Neutral to Drive while coasting at 55mph?
     
  10. jamarimutt

    jamarimutt New Member

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    Re: Neutral to Drive

    You can do this at any speed, back and forth, and nothing noticeable happens, other than the car gaining or losing speed.

    You can also shift from D to R or even hit P at any speed and you won't damage the car; as a protective measure it will shift, you guessed it, into neutral.