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Old 04-29-2009, 04:37 AM   #21 (permalink)
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I'm curious if a piece of thin sheet attached to the body between the hatch and the 1/4 glass area would straighten out that flow that is trying to wrap around and cause turbulance? Maybe have it stick up about an inch. It's a similar effect that happens on the end of airplane wings, and thats why they upturn the wing tips.
It's minimal on your car, but I know they have this on Nascars, etc, and it could help those with steeper rear window angles maybe?

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Old 02-10-2010, 12:11 PM   #22 (permalink)
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Quote:
Originally Posted by rkcarguy View Post
I'm curious if a piece of thin sheet attached to the body between the hatch and the 1/4 glass area would straighten out that flow that is trying to wrap around and cause turbulance? Maybe have it stick up about an inch. It's a similar effect that happens on the end of airplane wings, and thats why they upturn the wing tips.
It's minimal on your car, but I know they have this on Nascars, etc, and it could help those with steeper rear window angles maybe?
Thread resurrect...

Was this tried out?? I'm still interested in some type of small bump at the very edge of the rear of the hatch. I've read that this should allow the air to detach from the car and smooth out the wake, correct? Sorry, I'm still a noob here and I'm wanting to learn.
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Old 02-10-2010, 01:30 PM   #23 (permalink)
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A small "spoiler" at the end of the hatch could help a tiny bit or hurt a tiny bit. Unfortunately, outside of a wind tunnel, you'd never be able to measure what effect it has.

FYI, the Chevy Volt aero team determined a small rise in the trailing edge of their hatch helped a very small amount.

See: http://ecomodder.com/forum/showthrea...ures-4629.html
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Old 02-10-2010, 08:14 PM   #24 (permalink)
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thats sounds like a description of a duckbill type spoiler, like on the eg hatch
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Old 02-11-2010, 10:34 AM   #25 (permalink)
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Quote:
Originally Posted by MetroMPG View Post
A small "spoiler" at the end of the hatch could help a tiny bit or hurt a tiny bit. Unfortunately, outside of a wind tunnel, you'd never be able to measure what effect it has.

FYI, the Chevy Volt aero team determined a small rise in the trailing edge of their hatch helped a very small amount.

See: http://ecomodder.com/forum/showthrea...ures-4629.html
Yes, I've seen the Volt's rear.... I've been looking at it as much as possible to see what I can come up with. Also my friend has a '08 hybrid civic and his car has a very small spoiler at the tail end of the car.

I'm surprised that no one has really any data on a rear wing for the CRX's. I'm sure someone's tried something and has some type of results, whether their skewed or some-what plausible... Just thought I'd ask. I guess I'll have to do the tuff testing myself.

Oh BTW, I've removed my side mirrors.... Very weird...
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Old 02-11-2010, 01:29 PM   #26 (permalink)
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Quote:
Originally Posted by k.civic.f4i View Post
thats sounds like a description of a duckbill type spoiler, like on the eg hatch
I'm not sure what the strict definition of "spoiler" is, but the duckbill seems functionally different than the Volt's spoiler.

The Volt's feature is a "step" up - an increased angle compared to the preceding bodywork; the Civic's duckbill is an extension of the existing taper in the roof line a bit further out to slightly reduce wake cross section (and prevent flow from wrapping down onto the rear glass).

They're similar in that they both probably promote cleaner separation.
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Old 02-11-2010, 01:54 PM   #27 (permalink)
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Quote:
Originally Posted by MetroMPG View Post
....to slightly reduce wake cross section (and prevent flow from wrapping down onto the rear glass).

They're similar in that they both probably promote cleaner separation.
This is what I'm wanting to try to accomplish, keeping the air off the rear glass, and to promote cleaner separation... Like I said, I can test this, but my data is not very accurate since I'm not using precision instrumentation here.... I have a vacuum gauge, and a gas tank capacity gauge, whoa.... It's better than nothing.
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Old 02-11-2010, 02:21 PM   #28 (permalink)
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By rear glass, you mean the vertical panel?

I don't want to discourage you, but I doubt you're going to be able to measure any change, short of boat-tailing the car, or adding a really big (bad) spoiler.

Did you see the size of the effect GM measured on the Volt with their 5mm (IIRC) spoiler height?
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Old 02-11-2010, 02:23 PM   #29 (permalink)
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Quote:
Originally Posted by MetroMPG View Post
By rear glass, you mean the vertical panel?

I don't want to discourage you, but I doubt you're going to be able to measure any change, short of boat-tailing the car, or adding a really big (bad) spoiler.

Did you see the size of the effect GM measured on the Volt with their 5mm (IIRC) spoiler height?
I don't recall at the moment, but wasn't it barely measureable?

What else can I do to aero my CRX? I'm going to start a new thread, sorry for the hi-jack....
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Old 02-11-2010, 02:51 PM   #30 (permalink)
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Start it up! We'll continue the discussion there.

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