Interior Exterior
Q:
This added duct does not look like it would work. It directs more air to the low pressure side of the radiator. This may reduce cooling.
What Stan said.
The air intake in the front of the Elise passes air into the front of the crash structure. The air is then routed up through the radiator and out through the top of the clam via the vent openings in the front. The location of the NACA duct appears to allow air into the front top side of the radiator area - where the any air that is admitted via the NACA duct will pass over the top of the radiator, and not through it. There is no way that I can foresee that that duct can aid the cooling in any way, unless there is some kind of additional ducting behind/below the duct causing the air flow to make a 180 turn, enter the crash structure ducting, and make another 180 turn.
I'm sure that it would appear that it has lowered the running temperature, just the way I'm sure that adding Motorsilk, or Split Fire plugs creates improvements - you make a change that expensive, it damn well better help things.
If there' more going on under the clam shell, I'd like to know that, but in the mean time, I hope no one else copies this idea...
Some quick drawing - note in the photo below, the arrow appears to be pointing where the NACA duct is located. Note the black outline of where the radiator is located. I don't see how any air flow can pass into the duct and through the radiator...
A:
I think it looks actually looks pretty good especially since it's a black car. He put it there for a reason, and he is actually getting results. I don't think he is trying to impress anyone who drives a Civic.
I think it's fine to mod and so forth. But it may or may not be the case that this mod is working. Scientific method and so forth. From the standpoint of theory, not only won't it help, but it may slightly hurt.