1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Cold Weather Performance with Grill Blocking

Discussion in 'Gen 2 Prius Main Forum' started by SageBrush, Jan 13, 2011.

  1. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,531
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    This is my second year blocking my grill. Last year I only blocked the top, and this year I included 2/3rds of the bottom. I hope I am erring on the side of caution in protecting my G2 inverter cooling. I have a SG that reports radiator temps. No spikes over 198F, and most of the time 184F.

    I take the car to work 95 miles away where it sits for a couple of days in cold soak, and then I drive it home. This week ambient temps were 25 - 40F during driving, roads were dry, humidity low, and air thin at 6000 - 7500 feet. I set the cabin temp for personal comfort after the ICE has warmed up past 150F or so. This takes a couple of minutes. Round trip MPG: 58.5.

    This is about 5% less than my typical in moderate spring or fall weather, and I am delighted at the minor hit in fuel economy. Not exactly new news, but the astonished reports of EV drivers :rolleyes: losing 1/3 to 1/2 of their range in the winter is making me feel smug.
     
  2. Hal W

    Hal W New Member

    Joined:
    Sep 26, 2010
    872
    53
    0
    Location:
    Grand Forks,B.C. Canada
    Vehicle:
    2006 Prius
    Model:
    II
    So that looks about perfect. I have been blocking 100% without a scan gauge. I think I will remove the bottom row. Are you not blocking the lowest row? H
     
  3. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,982
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    I've got both grills fully blocked and still it takes 20-30 min. to reach 70-80C coolant temp. The thermostat doesn't open fully until 85C so I suspect there is minimal flow through the radiator. I leave the heater in "auto". Have to use front defrost for the first 5-10 min. so I can see where I'm going (this is kind of necessary ;) ). If I can get clear road with conditions good enough to go 70 km/hr (about 45 MPH) I can get piping hot air out of the heater in a few blocks. Otherwise it can take 5-10 min. before I get nice heat.

    You can reduce the mileage hit by turning off the A/C (auto) whenever you stop, allowing the engine to stop at lights.

    I don't bother to plug in the block heater as it has minimal effect at these temperatures (-25C out there now).
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    109,200
    49,652
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i just blocked my grille for the first time. made two 15 mile round trips to work so far, temp in the 20's. haven't noticed a difference, hanging in around 50mpg.
     
  5. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,531
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Hi Hal,
    Keep in mind my car is a G2. Air intake has an upper and lower section. I completely block the upper section, and the upper 2/3rds of the lower section.

    The blocking pattern for the G3 Prius intended to keep air flowing towards the inverter radiator will be different. Ken from Japan posted a thread on the topic, and is the most informed I think.
     
  6. Hal W

    Hal W New Member

    Joined:
    Sep 26, 2010
    872
    53
    0
    Location:
    Grand Forks,B.C. Canada
    Vehicle:
    2006 Prius
    Model:
    II
    Mine is a G2 as well, SageBrush. Hal
     
  7. BAllanJ

    BAllanJ Active Member

    Joined:
    Dec 9, 2008
    667
    78
    0
    Location:
    Kingston Ontario
    Vehicle:
    2017 Prius
    Model:
    Two
    I block all the top and 2/3 of the bottom and I use the block heater for a couple hours before heading out. I think the ebh helps even at the -20c we had this morning ... takes at least several minutes off the warm up time. I use the heat sparingly until it gets to 70c if I can take it and the windows aren't frosting... 10 to 20 minutes. I think I'll block the rest of the grill tomorrow so I can get more heat into the cabin.
     
  8. Hal W

    Hal W New Member

    Joined:
    Sep 26, 2010
    872
    53
    0
    Location:
    Grand Forks,B.C. Canada
    Vehicle:
    2006 Prius
    Model:
    II
    I am sure you can block it completely with -20 temps. My car is in Victoria blocked 100% without issues. I have had it blocked complete at +12c without the light coming on.Not sure how far I can push it? H