grills blocked by insulating material

In short people here have used advanced instrumentation to show that blocking outside air intake through the grills in very cold weather keeps the engine within the most efficient operating temperature increasing mpg when it's colder than 40-50F.

Use the search engine you ll see some very instructive photos and one very long thread about it.

 

<div class='quotetop'>QUOTE(jarhtmd @ May 12 2007, 02:35 PM) [snapback]440671[/snapback]</div>

There is a wealth of information (and pictures) on this thread http://priuschat.com/index.php?showtopic=2...l=blocked+grill (found by searching on "blocked grill"). [Search lesson included at no charge.] A member from NY made a video.

In the opinion of those who did it, yes it is a good thing. It kept my winter mpg in line with the lifetime average. Keeping the ICE warmer causes it to run less when stopped. A blocked grill can be unnoticed until you get real close--it all depends on technique and materials.

 

It also helps in hot weather. One blocked inlet crossbar reduces the inital mpg loss usually experienced when first taking off.

 

<div class='quotetop'>QUOTE(Old Marine @ May 13 2007, 12:15 AM) [snapback]440914[/snapback]</div>

Has anybody else grill blocked in warmer weather, and if so how much.

Other than the foam pipe insulation pushed in the crossbars are there any other methods such as blocking the radiator directly or is that a bad idear (that is what we used to do years past).

 

<div class='quotetop'>QUOTE(efusco @ May 13 2007, 05:15 AM) [snapback]440988[/snapback]</div>

I have a scangaugeII and monitor the ICE temp. Never seems to above 185F. If I block the uppers will this change of wil it just not cools so fast. Also is monitoring the ICE on its own OK, does this give you an idear of what the MG is doing, as I cannot monitor this?

Thanks

 

I took mine off a couple of weeks ago when I did the full Zaino treatment, expecting to leave it off for the season. Last weekend, with overnight lows in the upper 30s, I put it back on. I forgot about it until it hit me, in a flash, on the way home Friday afternoon in near 90-degree temperatures ... Hey, I still have the grill block on! Not to fret -- I checked the ScanGauge and the maximum temperature for the run was only 202F.

Two things to mention here. First, I keep one slit in the bottom grill open to provide a little air flow, especially to the inverter cooling system, except during the winter. Second, Friday's drive included a lot of ICE-off time (as most do these days) -- a lot of pulse and glide and sitting at idle in traffic. Continuous running of the ICE (e.g., highway driving) would, of course, cause more heat buildup.

 

It's been almost 80F in the mornings. The car sits outside all day and it is in the 90s going home. The upper grill is blocked, the climate control set around 78F (I move it up & down a few degrees to keep it comfortable) and the fan hasn't come on. MFD indicates mpg between 55-57.5 for the tank. Commute is 35 highway miles. Today's traffic jam knocked almost 2mpg off the average at half a tank. If the numbers hold, this is a 10% increase over my lifetime average. I am losing at least 1mpg on the way home every day but make it up (and sometimes more) in the morning. I can confirm that just running the ac does not cause the ICE to start or run.

 

<div class='quotetop'>QUOTE(JimN @ Jun 27 2007, 07:36 PM) [snapback]469130[/snapback]</div>

Wow, so we're looking at possibly year-round upper grill block for the cooler climes?

 

<div class='quotetop'>QUOTE(Tyrin @ Jun 27 2007, 11:08 PM) [snapback]469192[/snapback]</div>

Yes, as recommended by Fire Engineer. IMO it is safe to block the upper grill until the fan turns on. Once that happens I'd remove one piece at a time until the fan no longer activates. Beats carrying the stuff in the small cargo compartment.

 

<div class='quotetop'>QUOTE(JimN @ Jun 28 2007, 08:15 PM) [snapback]469760[/snapback]</div>

Is it obvious when the fan comes on? I have blocked mine for the past 3 months although the summer this year in the UK does not seem to be happening yet.

 

<div class='quotetop'>QUOTE(gazz @ Jun 29 2007, 06:11 AM) [snapback]469913[/snapback]</div>

I've never heard it. One of our pilot members said it sounds like a jet engine.