I've now hard anodized the vent. The anodizer warned me that standard "type II" color anodizing will fade from UV. Hard anodizing will not. The main issue is that the color
is dependent on the aluminum alloy's chemistry, so it will vary for different aluminum alloys. I got lucky that the anodizing matched the paint.
I like how you can see the charger fins through the vent!
Yes, Type II color anodizing fades, & also varies slightly with alloy, but all the different alloys' HARD ano. I've seen is some shade of charcoal & WAY more durable than Type II. You really only see a color difference if you have the two alloys side-by-side.
Good idea that this could also apply to the gas version. Maybe post it on that forum too, like I did for my main wheel/tire thread. Or maybe just post a link to this thread over there.
I'm going to have to fess up on this. The vent is not my work; I only softened the edges, anodized it and installed it.
The folks who should really have credit for this vent are RaceLouvers.
The make louvers specifically for a variety of cars, including the Fiat 500. I just used one side.
What most impressed me about them is the company developed these vents for maximum airflow. They have real wind tunnel data on the vent's effectiveness.
My testing of the 500 verified that they really work. All of the cooling air goes through this vent. The alternative routes ( under the car and the wheelwells ) are completely blocked on my car. I've done tuft testing and pressure testing with them and monitored the cooling using my scanner while doing multiple acceleration tests on a hot day. No problem with overheating.
So, it's starting the rainy season - thank god!
That vent is a giant hole in my hood, and I'd like to reduce the amount of water that gets in.
In general, it will be a removable cover, in the form will be one of those backward facing cowl-type vents. I figure the weather will be cooler, but I'd still like some airflow.