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Blocking and unblocking the grill?

Discussion in 'Gen 2 Prius Fuel Economy' started by homerj742, Apr 6, 2007.

  1. homerj742

    homerj742 New Member

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    Excuse my ignorance, but what is the purpose of blocking and unblocking the grill? Keep the engine from getting too cold during the winter months?
     
  2. daveleeprius

    daveleeprius Heh heh heh you think so?

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    <div class='quotetop'>QUOTE(homerj742 @ Apr 6 2007, 06:00 PM) [snapback]419085[/snapback]</div>
    Some people live in extremely cold climates, with temps in the 20s or less most days. In those cases, blocking the grill will help the engine warm up and stay warm. In the Seattle area, the temps never go below the mid 30s in winter, so I wouldn't bother blocking my grill.

    And it's important *Not* to block your grill if the weather goes above 60 degrees outside unless you want to damage your car. It's safer to leave it as designed than to start mucking about with it. I'd rather have a long lasting car with slightly lower gas milage, than higher gas milage and damage to components down the road.

    Dave
     
  3. hdrygas

    hdrygas New Member

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    Evan in a mild climate with temps in the low 40's you can see the ICE and Fluid temps dropping below 160 F where you can stay in Stage 4. At freezing at a long light it can drop to the 120's. We don't often get much colder weather but when we do the radiatior blocker makes a difference. I am not sure what outside temp you need to unblock at. I do not think that above 60 you get anything more than a bit of help on warm up. I would add that I can watch the various temps and my radiator blocker zips and unzips. I will take it off at the end of the month and put it back on in late September early October.
     
  4. SomervillePrius

    SomervillePrius New Member

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    I agree, blocking the grill has moderate effects even with temperature in the 40s. Below 30 it makes a large effect with a side effect of warming up the cabin faster. Only down side is that outside temperature tends to read a little high with the grill blocked.
     
  5. JimboK

    JimboK One owner, low mileage

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    Even in more moderate climates it helps winter fuel economy. After I bought my ScanGauge I was quite surprised, for example, at how quickly the cabin heat robbed heat from the ICE -- 10 degrees or more just sitting at a red light. The cooler the ICE, the more it wants to run to keep itself warm. Grill blocking goes a long way toward preserving that precious heat and reducing instances of the ICE running when it otherwise doesn't have to.

    The damage Dave refers to is from overheating the ICE and the inverter. Many of us with the grill block monitor the coolant temperature with devices like the ScanGauge. On the few occasions in some of the warmer days late last fall or early this spring where I've seen the temp creep up over 200F, I just removed one piece of the block. That little bit of air flow easily kept the coolant temperature in the low 190s and below.

    I respect Dave's "better safe than sorry" approach. As for me, I am comfortable with the block as long as I can watch the coolant temp. I've seen no reports of problems from anyone who has used it.
     
  6. Frank Hudon

    Frank Hudon Senior Member

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    50/50 mix of antifreeze and water with a 15 lb rad cap the system is good to about 245F before it will boil. I wouldn't feel confortable running it that hot but 200 is where the cooling fans come on and when it does the system cools back to the 185-190 range very quickly, so unless the cooling fan system is no operative you hardly have anything to worry about. To check the cooling fans, turn on the A/C and listen you'll hear them running.
     
  7. Tyrin

    Tyrin New Member

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    <div class='quotetop'>QUOTE(hdrygas @ Apr 6 2007, 07:09 PM) [snapback]419104[/snapback]</div>
    What kind of block do you have that zips/unzips? :eek: Where can I get one? All I've seen on other threads is the pipe insulation...

    EDIT: I went to your website. The blockers look awesome! You should sell those! I would definitely consider buying...
     
  8. homerj742

    homerj742 New Member

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    I'm thinking of blocking the grill for tomorrow's trip, 60 + miles in 30 degree temperature.

    Now, since I do NOT have a Scangauge, I will only be blocking the top grill, and 1 out of the 5 spaces on the bottom grill.
     
  9. icarus

    icarus Senior Member

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    You'll be fine, even if you only leave the bottom slit open. In fact, with an OAT ~30f you will have trouble keeping the ICE ~185 even with all but the bottom section blocked.

    Icarus