Grill block on 2001 Civic HX - Too much?

[darcane]

Made up a Grill block for my new Civic:


It's hard to see, but it completely covers the lower grill opening leaving only a few gaps around the emblem for an air inlet.

I've been monitoring temps with my Ultragauge, and it went from a rather constant 188°F to fluctuating from 199°F to 207°F. I've been contemplating cutting a hole in it, but since I haven't heard the fans kick in and it's still in the warm summer months, I'm leaning toward leaving it.

Any thoughts?

[Daox]

If the temperature is fluxuating that is the fan kicking on and off. I'd probably cut a hole in the bottom.

FYI it is almost always better to start by blocking your upper grill and then moving on to blocking some of your lower grill.

[PaleMelanesian]

I agree with Daox. 206 or 7 degrees is where Honda likes to set the fan trigger. Open it up a little.

[darcane]

Originally Posted by Daox

If the temperature is fluxuating that is the fan kicking on and off. I'd probably cut a hole in the bottom.

FYI it is almost always better to start by blocking your upper grill and then moving on to blocking some of your lower grill.

I discounted the fan because I couldn't hear them, the fluctuation seemed to correlate with vehicle speed, and I thought there was no way they would turn on at that low of a temperature. Sure enough, they do. Somewhere around 200°F +/- a little.

Yeah, I know upper grill is preferred. But I preferred this method aesthetically. Making an upper grill block that didn't look goofy would have been far more difficult.

[jalmir]

Originally Posted by darcane

Making an upper grill block that didn't look goofy would have been far more difficult.

Blocking the back of the upper grill would be fine and wouldn't look goofy

[darcane]

Originally Posted by jalmir

Blocking the back of the upper grill would be fine and wouldn't look goofy

I couldn't get behind the upper grill without removing the entire bumper cover, and many of the fasteners underneath the bumper are damaged (scraped on curbs) making it difficult to remove.

Also, I found it rather ineffective on my truck to put a grill block behind the grill. Quite a bit of air was still flowing past it.

All in all, it would have been a large effort to get little, if any gains. The upper grill has very little surface area open to allow air through. Even though it has a straight shot to the radiator up there, I'm apparantly still heating up enough to engage the fan.

[brucepick]

Here's a pic of my '97 HX grill block. Sorry the opening is on the far side away from camera, but you can see it goes right up to the license plate. This was an early photo of it. Now has an "L" shaped leg added that extends below the license plate, towards the center of grill. Also I extended it on top, bottom and outside edge, about 1/4 to 1/2 inch bigger on each of those cuts. I needed that in summer for sufficient cooling. Upper grill is blocked but only on driver's side, radiator is on the other side.



In winter, I used to block up the lower grill openings with foam pipe insulation between the slats. I expect to cover the opening you see completely from about December - February. I found in winter I could block all the lower and just leave the upper open. I watch engine temp on the ScanGauge so I see what the temperature is doing.

In my 6th generation Civic the radiator fan is on passenger side and a/c condenser and catalytic converter are on driver's side. So for cooling you only need to open the passenger side. If you block the a/c side and run the a/c, the a/c condenser fan comes on and will blow air through there. Mine worked great for 3.5 years and finally the compressor froze up but I don't think that was due to the grill block.

[turbovr41991]

That upper section does not look like it flows much air to begin with. I am still wondering what kind of hole works best. A larger squarish hole like bruces works really well as the radiator is on that side, but it would be easier to make a longer more retangular air duct in the 96-98 bumper. In the sort term I am using duct tape, but want to redo it with a second bumper to make it apear factory and smooth.

[darcane]

Originally Posted by brucepick

Here's a pic of my '97 HX grill block. Sorry the opening is on the far side away from camera, but you can see it goes right up to the license plate. This was an early photo of it. Now has an "L" shaped leg added that extends below the license plate, towards the center of grill. Also I extended it on top, bottom and outside edge, about 1/4 to 1/2 inch bigger on each of those cuts. I needed that in summer for sufficient cooling. Upper grill is blocked but only on driver's side, radiator is on the other side.


In my 6th generation Civic the radiator fan is on passenger side and a/c condenser and catalytic converter are on driver's side. So for cooling you only need to open the passenger side. If you block the a/c side and run the a/c, the a/c condenser fan comes on and will blow air through there. Mine worked great for 3.5 years and finally the compressor froze up but I don't think that was due to the grill block.

Thanks Bruce! This gives me a good idea how much to open it up.

7th gens are the same basic layout with the radiator on the passenger side, A/C on the drivers side. I'd guess I get less airflow than you through my upper grill though.

[darcane]

Well, looks like I was wrong again. The 7th Gen Civic has a full width radiator with an A/C condensor in front of it. The way the fans were mounted made me think otherwise at first glance, but once I got to looking closer I figured out I was wrong.

Anywho, I put two holes in like so:


While the time it takes to trigger the fans is much longer, it still climbs and flips on. So, I'll have to go a bit larger yet.

I am a little concerned about how much restriction the condensor has on air flow at this point. Nearly every fin on the condensor behind my grill block is bent back from road debris hitting it.