Lunar, I just remembered that a few days ago
cfg83 started
this thread showing how he made a spring loaded grill block. At small speeds it is in the open position, but when going faster the wind closes it. When slowing down it opens again. This is pretty much what you are looking for, only your thread was about the block being stationary.
I've been thinking about both types for my car, since they are much less complicated than an electromechanical opening mechanism, but my diesel is almost always running cold. Today is the first day here with temps around 15*C, so maybe shortly I'll hear my fan (haven't heard it yet) and start unblocking the grill and thinking about something permanent. I really wonder how this static grill "shield" will perform. When are you going to try it?
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e·co·mod·ding: the art of turning vehicles into what they should be
What matters is
where you're going, not
how fast.
"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell
[Old] Piwoslaw's Peugeot 307sw modding thread