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Weather Spotter 08-15-2010 08:59 PM

How to make an upper grill block (for a Matrix)
Here is what I had made last winter:

Not a bad grill block but I did not like having the logo open (it stuck out too far to go over though). It came off in about 3 seconds (nice pop with a screwdriver).

First thing I did was to make a cardboard template. You can also start with paper, but my shape was not that complex so I went with cardboard.

I took an old box and cut it to the height I wanted (top to bottom), then I taped it up on the car. Next I marked the rough edge (out about 1/2 an inch to give me room to fine tune the edge). Once that was done I marked the edge with a pencil and cut the exact edge I wanted. Repeat on the other side. I waited to do the other side so if I screwed up my cut I could just move the cardboard over and inch and try over.

Next place your template on your grill block material. I used some galvanized steel (same as I used for my wheel skirts). If sheet steel is not handy try colorplast.

Trace your template onto the grill block material (if using metal mark the shape and make a 3/8" larger line). Cut the line (use the outer one with metal). With colorplast skip this next step.

If using sheet metal bend along the traced line (inner one). Use vice grips to bend on the line up past a right angle. Then hammer over the tabs (pound it flat).

This will make the edge rounded and not sharp (does not scratch paint or cut your hand when reaching for the hood release).

Now check your fit on the car:

If you like the results you can attach it (if not go back and fix it). I used self tapping sheet screws to hold mine on (screwed into the holes that were filled in on the back).
Other ways of attachment that worked for me:
Zip ties, nice for testing, not so good of looks.
Flat headed bolts (see the first picture).

Paint as desired.
I ran out of primer and silver paint so I will post pictures when it is done.

comptiger5000 08-15-2010 09:11 PM

Looks good! And I like the more aero covers for the fog light holes.

Weather Spotter 08-15-2010 09:22 PM


Originally Posted by comptiger5000 (Post 189039)
Looks good! And I like the more aero covers for the fog light holes.

I made the fog light covers out of colorpast a few days before I made the wheel skirts. I might remake them out of sheet steel though as I do not like how thick the colorplast is (I can not thin down the leading edge). I might just fill the holes in with fiberglass, I am not sure.

comptiger5000 08-15-2010 10:01 PM

I'd personally just re-make the covers in sheet metal, rather than filling the holes. That way, if you ever wanted to use them for cooling ducts, or to put lights in, you could simply modify the covers to accommodate while retaining good aero, rather than giving up any potential future use of the holes by glassing them in.

gone-ot 08-16-2010 10:16 AM

...make them (lamp and upper grill fillers) out of carved styrofoam, that way you can maintain the basic aerodynamic "lines"

...then use velco strips (in back) to hold them in place for easy A-B-A tests.

Weather Spotter 08-16-2010 10:24 AM

I think that the change is way to small to show results with ABA testing. I might make covers out of steel but the more I look at it, what I made should get me 95% of the benefit with 30% of the work that new ones would take.

Weather Spotter 08-17-2010 12:52 PM

More Pics:

both sides are primed:

and the back side is painted:

I went with black as it is cheaper than the silver that matches my car. Also if I do not like the sliver grill bock I will paint it black or charcoal.

When I went into town yesterday I was watching the SG temp read out and it did not go over 184F. Out side temps were 75 and very windy.

Weather Spotter 08-19-2010 06:45 PM

On my trip yesterday (320 miles) I watched the ScanGauge temp readout, all was fine. It never went over 186 for more than a min (once it did was one steep but short hill I did a 25mph pushed it to 193). Outside temps were between 85F and 68F. Sunny and then some rain (with temp drop). This tells me that blocking the upper grill year round should not be a problem unless I vist death vally.

Daox 08-19-2010 06:54 PM

I never had any problems with my upper grill blocked on my Matrix year round. During winter, I ran a full grill block. Again, no problems at all, and I watched the SG to make sure.

Weather Spotter 08-19-2010 09:50 PM

Last winter I had a full grill block but as the temps got warmer out (above about 40F) the fan was comming on all the time so I took them off. Now I see that I could have left the bottom one on. I remade the upper grill bolck though because I did not like the looks of the old one. It had the toytoa logo area cut out (which still lets air through) and I did not like the look. So I removed the logo (came right off with a screwdriver) and make a full block. I will be painting it to match my car (silver) which should also look better than the glosy black.

Did you see how much of the bottom one you could block all year as well?

I want to make the bottom one able to be opened/ closed from the drivers seat, how should I do this?

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