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Stan, i think we're on the same page. I posted that as an example of the many 'cold air intake' devices that have been around for years (and apparently selling very well, I guess).
The science and the folklore seem to agree that colder intake air is a good thing. It's just a question of how to get there.
There's been much debate in the Miata community over whether things like the pictured device actually get the job done. Here's a guy who found they don't, after running some tests and posting a video.
Which has me wondering about the turbo hats as a way to get there for our cars. Here's an off-the-shelf bolt on that easily gets half the job done. It isolates all intake air from the engine compartment and terminates in a fitting that connects easily to other ducting.
It would seem an easy thing to hook up some hose, drill some holes into the wheel well, and fabricate something to filter out dust, leaves, and tree limbs. But I've never seen anyone do that and I'm wondering why not.
Emory does something similar with his louvered panels (and he got the idea from some factory racing 356's back in the day. But I think those just bring air into the engine compartment and aren't plumbed directly to the carbs) :
What am I missing here?
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