well had the wife's Prius out today and with the temps in the low 70's and the whole thing blocked off I decided to try what I believe to be the sequence for removal of the blocks. Driving around had the ICE and the thermos both in the 95 97C range so pulled over and took out the upper blocks and for the rest on the drive, about an hour in mixed traffic had the temps of both the ICE and the thermos in the 85-87 range which is where the thermostat starts to open. So will leave the lower grill blocked till the ICE temps get into the low 90's. As the inverter section of the rad has the openings in the belly pan if it gets to hot just unblocking the upper is sufficent to keep the temps in the normal range. If the temps spike up I might consider taking out the lower block but at this time all looks normal. And I did one good hill with the uppers out and the temps never exceded 87C
<div class='quotetop'>QUOTE(Frank Hudon @ Apr 6 2007, 07:57 PM) [snapback]419114[/snapback]</div> This is good information to know, thanks! I bet that you can keep at least one strip in all year long. If cars can drive uphill in Death Valley at 120F, they can do ok with a strip or two of insolation under less severe conditions you would think
<div class='quotetop'>QUOTE(Tideland Prius @ Apr 6 2007, 10:28 PM) [snapback]419230[/snapback]</div> if figured that out this winter when I couldn't get the temps up to more than about 67-72C by not having the upper's blocked, as soon as I blocked the uppers the temps were in the mid 80's all the time and the mileage went up almost 1 liter per hundred. So I'm saying bottom in first in the fall then the tops and then come spring tops out first followed by the bottom.
If I may add my recent experience, driving to/from New England. 4/4 Full block speeds 50-65 MPH, outside temp 32F, terrain mostly flat at first, engine temps 196F-202F, rising with speed. Start mountain driving through PA, temp 42F, climbing and falling road terrain, speed 55-70MPH, engine temps average 200F, max at 206F. Stop for gas, remove 1 block on lower grill, back to same conditions above, temps down about 10 degrees F. Coming back was a full block, even in very windy and snowy conditions the temps stayed up with the full block, only rising to the highest on long ascents. So upper or lower seems to be good for about 10 degrees F. Wayne
How can you find out those engine coolant temps? I wish the Prius had a temp gauge built in,(also a compass would be nice!) instead of the stupid snowflake when it's below 37 degrees. Do you guys have some sort of 3rd party device that gives you temp info? Thanks in advance for the knowledge update, Joe <div class='quotetop'>QUOTE(FireEngineer @ Apr 9 2007, 10:24 AM) [snapback]420260[/snapback]</div>
Does any of this void the warranty? Also, does Toyota have anything to say about it like "interesting" or "don't do it"? Also, since you guys are into maxing out the mileage, anyone have an opinion on acetone? I personally believe that some of the good results people have gotten are due to dissolving fuel lines and burning them as fuel. I acknowledge I could be wrong. Apologies if I'm being a troll or making like Moriarty with the negative vibrations.
<div class='quotetop'>QUOTE(joe350gt @ Apr 9 2007, 09:00 PM) [snapback]420515[/snapback]</div> Many of us have a ScanGauge. <div class='quotetop'>QUOTE(sharkmeister @ Apr 9 2007, 09:35 PM) [snapback]420529[/snapback]</div> I haven't asked Toyota, but if it doesn't harm the car it shouldn't affect the warranty. I can't tell you a thing about acetone.
I use CAN-view on the 2k4 and I use the Mini Scanner on the 2k3 and monitor the temps of the ICE and the MG's and the Inverter for the MG's. Also Toyota doesn't comment on anything we do with the car. Have a look at the thread on the fuel tank dissection and then decide if you want to pour acetone on the liner and chance damageing it.
<div class='quotetop'>QUOTE(sharkmeister @ Apr 9 2007, 08:35 PM) [snapback]420529[/snapback]</div> No need to apologize. Many of us are trying to decide how far to push the envelope and everyone's experiences are helpful. <div class='quotetop'>QUOTE(joe350gt @ Apr 9 2007, 08:00 PM) [snapback]420515[/snapback]</div> A GPS unit is more useful and takes up as much space as a compass.
So what thickness of pipe insulation are people using? I plan to head to Home Depot soon if this cold snap continues. B)
<div class='quotetop'>QUOTE(zendriver @ Apr 9 2007, 09:18 PM) [snapback]420621[/snapback]</div> get the stuff that fits 1/2" copper water pipe.
<div class='quotetop'>QUOTE(Frank Hudon @ Apr 9 2007, 11:19 PM) [snapback]420623[/snapback]</div> Turns out there are two thicknesses...and Home Depot only had one thin stick left (3/8" thickness vs. 1/2"). The 3/8" worked better on the narrow lower one ('til I ran out), while the 1/2" thickness was nice on the upper. Can't wait to see how it does tomorrow: HI 37F LO 27F, with wet snow. Should help a bit, though worst of winter is past.
<div class='quotetop'>QUOTE(sharkmeister @ Apr 9 2007, 08:35 PM) [snapback]420529[/snapback]</div> Shark: I now use the CAN View, which I believe is an outstanding product, especially for 04 and 05 Prii, which have the analog MFD and don't require an additional screen, as the newer cars would. I experimented rather extensively with using acetone in my previous car (a G35 sedan). I noted no ill effects (that I could detect) well over a year after I terminated the experiment. I terminated the experiment after several months of of using acetone at the generally recommended dose (which I don't recall at the moment) because I saw absolutely no effect at all on my mpg. None. I would under no circumstances even remotely consider putting acetone in a Prius with the soft fuel tank bladder. Acetone is a brutally active solvent which I've seen remove paint and varnished oil from inside an engine, very quickly (I rubbed an acetone soaked cloth in the oil filler of a varnished car -- varnish came right off). If I actually had a dream about putting acetone in a Prius, I'd call it a nightmare. . .
I figure on leaving the top opening blocked more or less forever. The bottom lets the *vast* bulk of air in, toward the right places [i.e. the inverter section of the radiator] and to me, making sure that's happy takes priority. Then again, much depends on the air flow path in the nose before it actually heads through the radiators. . _H*
opening the top pressurises the area behind the grill and what air that gets thru the rad at this point in time and OAT keeps the ICE and inverter and MG temps in check. The air that doesn't go tru the rad exits the area via the cutouts in the belly pan. When the ICE temps rise into the low 90's then I'll pull all the blocking out and put it back in the fall.
<div class='quotetop'>QUOTE(Frank Hudon @ Apr 10 2007, 10:51 PM) [snapback]421358[/snapback]</div> well good info to know as i thought that the lower should be removed first but only because its less effective for removing heat in the system. right now, i am in a position where the weather is too up and down. right now its 45 and rainy, Friday, it was 80 and sunny. i did remove two rows on the bottom a few weeks back and rarely see water temps above 194º so, we will keep it that way until i see 200. but without CANVIEW and using Scangauge, only have water temps to monitor. with CANVIEW, i would be more daring as MG temps can be monitored as well
<div class='quotetop'>QUOTE(DaveinOlyWA @ Apr 12 2007, 02:49 PM) [snapback]422203[/snapback]</div> So far, when I was looking at them both at the same time, I never saw more than 2F degrees difference between coolant and engine temperatures. I've been just looking at coolant temperature lately. Since getting CAN_View working about the first of the year, I've never seen the temperature above 194F myself. I do have the lower grill unblocked now though. Dave M.