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Old 05-12-2009, 06:52 PM   #23 (permalink)
vtec-e
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Join Date: May 2008
Location: Ireland
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De Yaris - '04 toyota yaris T2
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Quote:
Originally Posted by daqcivic View Post
The concern with having the grill block recessed is that it may create (or increase) a static, high-pressure pocket of air at front edge nose where the grill is covered up, slowing and/or detaching the airflow across the nose. I do not think it actually does this to any significant degree, as so many very aerodynamic cars seem to have recessed false-grill sections, as well as recessed pockets for fog lights or faux cooling ducts (which should be even worse)--see the new E-class coupe with its .24 cD.
I've recently trialled a flush mounted lower grille block instead of the recessed one that just replaced the original grille. I've left the opening the same and temps have gone from 82 deg c to 88 deg c. What you've just said is exactly what i was thinking! The pocket of air must be getting compressed and going through the opening with more pressure. I might flush off the fog light blanks to see what mpg improvement i see.

ollie
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