My ugly grille block
 

I spent the evening blocking my non-functional fog grilles (and a small amount of the functional grille). It sucks and I'm probably going to tear it off in the morning before I drive to work.

I cut Coroplast to shape and then curved straight pieces of coroplast wire frames to make it match the curve of the front end.
https://lh6.ggpht.com/ronanian/SJES73...8/IMG_1568.JPG
https://lh5.ggpht.com/ronanian/SJETBk...8/IMG_1570.JPG

Here's what the car looks like without them:
https://lh6.ggpht.com/ronanian/SJETLa...6/IMG_1572.JPG

Here's the filler that goes between the grille and the coroplast to make it nearly flush:
https://lh4.ggpht.com/ronanian/SJETG0...6/IMG_1571.JPG

Here's one installed after I had attempted to match the car's blue. It looks pretty decent in this pic but it really doesn't look as good IRL.
https://lh6.ggpht.com/ronanian/SJETQI...6/IMG_1576.JPG

Here's them both installed after painting them black and clearcoating them. I overdid the clearcoat, so the black, which was pretty decent, got really blotchy. Also, I didn't get them flush like I wanted.
https://lh3.ggpht.com/ronanian/SJETTh...6/IMG_1579.JPG

How can the clearcoat mess up the underlayer?!
If it turned white, maybe it's humidity or something.

Of all people here, I thought you would've sealed
the top intakes first for aero...

Consider polycarbonate. Available at Home Depot. Tougher than plexiglas. Avoids having to match colors. Thin polycarbonate (or plexiglas if that's what you've got) should be able to make that bend without heating. Protect the edges with clear plastic strips to keep from marring the finish underneath. For the vast general public, that tends not to be very observant, it will look unmodified. Plastic lens will eventually degrade with scratches and whatnot, but that should age with the car.

I would not close lower openings before closing upper openings. Fairing in the upper openings allows the air to slide over the hood smoothly. Leaving the lower openings open gives air that hits the lower bumper a place to go besides under the car. (It may still go under the car, but it will have done something useful along the way) But fairing in the upper openings is harder to make look good.

The clearcoat didn't mess up the underlayer. I put it on too thick and it was no longer clear in those spots. I suppose humidity could be part of it too...it was rather humid.

My upper grille is stealth-blocked; the blocking is invisible, behind the grille. It doesn't help airflow as much as if I did it out front, but it does not allow air to flow into the engine bay there and blocks the factory cool air intake, forcing it to get warm air from behind the radiator.

I can't block in front of that grille because I'm incapable of coming up with any result that won't attract attention. I think I can do these fog grille blocks without making it stand out too much, but it's going to take more effort.

I was thinking of taking these steps:
- Remove one layer of styrofoam backing so everything sinks in.
- Add layers of coroplast (thinner than the styrofoam) to make it come up flush. I could laminate them with glue and/or wire them together.
- Top layer either gets flat black paint, flat black Plasti-Dip spray, or I could laminate on some EPDM rubber roofing.

More on the upper openings: I could conceivably fill the slats with flat black styrofoam gap-filler made for filling gaps around house doors and windows. I'll have to look into that some more.

Also, I have a nice piece of polycarbonate, it's even tinted...but I want to save it for my truck, it's exactly the right size to do my truck's whole grille, and I think it would be less noticable there. I'll have to consider it some more for this car.

Ok, here's what it looks like in the daylight. The white blotches are thick clearcoat on top of otherwise decent black. The lines are where the metal wires are, which looks terrible in daylight...definitely going to need to laminate another layer on there.

https://lh6.ggpht.com/ronanian/SJG2gy...6/IMG_1582.jpg

what you might do is try to find some clear plastic packing material, doesn't have to be very thick, just something that will keep it's shape when backed

after you cut it to shape spray in the desired color ON THE BACK... when the paints dry, depending on its darknes overcoat it with black or white, in this case i'd say black, to keep it from shining trough, although that might not be needed as there's not light comming from behind.

instant deep gloss finish, the paint itself is protected from the elements, and even when it's scratched the paint itself won't be damaged.

you could clearcoat it fron the front for more gloss, but, well perhaps better not ;)

than again, i'm sure when you get the paint right on these blocks they'll look really nice!

You just put the clear coat on way to heavy. You want thin coats of paint. Lightly sand with some 220 grit sandpaper. Give about 3 light coats of black then 2 or 3 light coats of clear.

Say your painting something white and making it black. You don't want to cover the white in 1 pass. You want to put thin coats on to cover the white.
I would say re-paint it and it would look pretty nice.

:thumbup: That's exactly it. I was hurried and not interested in trying very hard, it was late and hot and humid and I just wanted to be done. I hope to have time and supplies this weekend to do it right. Maybe I'll try to get the supplies sooner and work on it a little tonight too, but not try to finish tonight.

I'm not sanding, though. If that's involved then it's gone too far. :D

why clear coat at all? isn't your lower bumper (very lower) and your grill a flat grey kind of dull tone?

I would just paint it black and forget about it.