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Old 09-18-2020, 08:33 AM   #4 (permalink)
Vman455
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Pope Pious the Prius - '13 Toyota Prius Two
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Quote:
Originally Posted by M_a_t_t View Post
Are you saying 2 and 3 had a piece put back on (as in return to OEM)? Or are we just guessing a random mod?

Also there is a poll option...
Yep, just guessing a random mod based on tuft behavior. I will say that both mods are moderately-to-very common on Priuschat, but to my knowledge have never been measured by anyone using them (although Altered 1 is often claimed to "improve downforce" by people who fit it on their Prius).

Quote:
Originally Posted by JulianEdgar View Post
Baseline: Very good flow, isn't it? I'd be pretty happy with that.
I thought so too. I could see some of the movement of the outermost tufts that the camera didn't pick up so well, but I'll comment on what I think is happening after I pressure test (if that confirms what I suspect).

Quote:
Originally Posted by JulianEdgar View Post
Altered 1: I'd be reasonably confident you've added a fence/lip (eg a 1-inch high vertical plate or similar) that causes separation from the top of the hatch.
Bingo! Almost exactly right--I taped a 21mm high lip to the top edge of the window:



Quote:
Originally Posted by JulianEdgar View Post
Altered 2: A harder one. My wife (who has watched aero testing tufts for about 25 years) says the wiper has been put back on. I say the antenna has been put back on.
Yes, this one is more difficult. There's no disruption to the baseline flow pattern, but the tufts toward the trailing edge of the window are behaving slightly differently. (Actually, now that I look again the tufts at the leading edge have changed behavior slightly as well).
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