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Old 06-27-2020, 11:36 AM   #46 (permalink)
Vman455
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Quote:
Originally Posted by 4drviper View Post
Are these really just RICE??
(race-inspired cosmetic enhancements)
Of course not. They're completely invisible to anyone looking at the car unless they kneel and peer under it, yet most if not all manufacturers of passenger vehicles today use rear diffuser panels or, as is becoming more common in the last 2-3 years, a centrally-mounted muffler shaped to function as a diffuser panel. Toyota uses straightening vanes on all its cars since the 2010 Prius was introduced.

The idea that one has to have a full, smooth belly pan before even considering a rear diffuser is bogus. You can glean as much from Hucho's book; in particular the discussion of the Opel Calibra's front air dam cutout and rear diffuser (p. 189-90 in the 4th edition), where he writes:

Quote:
Finally, the central cutout in the spoiler may improve the flow at the end of the underbody (Fig. 4.82(d)), so that a diffuser can work more effectively.
(emphasis added)

As well as from the example of nearly every current production car (and a fair number of SUVs/crossovers) in the world.
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