Well, the brutally cold winter is gone, so yesterday I finally got around to making my grille block. Makes sense.
Here's a good look at how bad the stock opening is:
It went pretty easily, I just had to pull some retainers off the shroud above the grilles (around the hood latch) and could see right into the cavernous space inside the fascia. It looked like I could just drop the block in and secure it at the top center with a zip tie through two holes in a beam that was there.
I had a broken piece of plexiglass that looked about the right size. So I slipped it in, took careful measurements with my fingers, then trimmed one side straight and put it back in. It fit great. I managed to get my drill in there to put two holes in the top center... and shattered it. Maybe a flat surface and some masking tape would have helped, but whatever. Plan B was to find the 2x3 piece of coroplast I had bought God knows how long ago to make a grille block out of- last year's Plan A. I used the plexi mess as a template to cut it down then used the zip tie as a handle while I sprayed it black with my other hand. A windy driveway isn't a fun spray booth, but you can stay away from other things and the paint dries
fast. I slipped it back into the car, zip tied the top to the bracket and sealed around it with duct tape.
And here's what it looks like now:
I've only had one run with it, but the butt wind tunnel (a horrifying name for the areo equivalent of the butt dyno) says it's an improvement. I don't have a huge scoop ducting air under the car any more. Weather and traffic conditions are hard to account for, but a couple signifigant glides didn't lose speed the way I'm used to and I was seeing higher instant mpg numbers than expected with the cruise set to 62 mph.
Temps were higher at times. Normal temp is 177-179, and it got up there pretty quickly. A long uphill stretch would bring it up to the mid 190s, which it would take a while to come down from. Stopped in traffic brought it up to 205-206. I'm going to have to keep an eye on that as things warm up.
Quick and effective, neat and stealthy. I'm happy with it. Now I have to get on procrastinating my belly pan!