"PS9" (PS9)
12/24/2014 at 14:21 • Filed to: None
0
12|
"PS9" (PS9)
12/24/2014 at 14:21 • Filed to: None | 0
| 12 |
Every other Honda hatch down here (Central Florida) is starting to come with these. Some even come with a special plate.
Someone wanna explain what's going on? Is a mean trick being played on honda hatch owners or something?
daender
> PS9
12/24/2014 at 14:27 |
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They're "speed holes." They originally started with drag setups to help reduce drag caused by a non-diffuser rear bumpers and funnel more air toward the chute when deployed.
jariten1781
> PS9
12/24/2014 at 14:28 |
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This ain't new. Supposedly the rear bumper on these guys acts as a big high pressure air scoop and drilling it out is like a ghetto diffuser. They were running them at the strip back in the 90s and the guys doing so would swear up and down in was measurable in their trap speed. Never really looked into it.
T5Killer
> PS9
12/24/2014 at 14:30 |
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There a few here in NM not many but a few. What is funny is the 10sec and 11 sec hondas don't have it.
Twingo Tamer - About to descend into project car hell.
> PS9
12/24/2014 at 14:46 |
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They're to evacuate air. On some cars the back bumper basically acts as a little parachute. Someone following my Panda on a faster road told me my bumper starts pushing backwards due to the air pressure on it.
this is not matt farah's foxbodymiata
> daender
12/24/2014 at 14:52 |
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Is that thing AWD? Why is there a wheely bar on a FF hatchback???
Sam
> this is not matt farah's foxbodymiata
12/24/2014 at 15:24 |
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When the car accelerates it always transfers weight to the back tires, even in FF. That's why it's so easy to screech the tires in FF cars.
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Sam
> T5Killer
12/24/2014 at 15:25 |
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That's because 10 and 11 second Hondas use real, functional diffusers. These guys are going for form>function.
Luc - The Acadian Oppo
> PS9
12/24/2014 at 15:30 |
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mr2gud2u
> PS9
12/24/2014 at 16:26 |
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Does it really make a car more aerodynamic? It seems similar to the myth that lowering a trucks tailgate makes them more aerodynamic. I'd love to see Myth Busters test this out.
Cryptopygia - Front Wheel Drive is Best Wheel Drive
> this is not matt farah's foxbodymiata
12/24/2014 at 18:43 |
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Minimizing weight transfer off the front wheels. They're technically called "traction bars" in FWD applications.
http://www.speedhunters.com/2010/01/guest_…
Tohru
> this is not matt farah's foxbodymiata
12/26/2014 at 08:07 |
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A normal wheelie bar keeps the car from flipping over under full-throttle acceleration.
A FWD wheelie bar hits the ground MUCH sooner so it can limit the weight transfer off the front wheels and help the car grip the track.
gogmorgo - rowing gears in a Grand Cherokee
> mr2gud2u
12/26/2014 at 11:41 |
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I'd also kinda like to see this tested.
Drag reduction is mostly about reducing turbulence around and filling in the hole behind the car. Forward profiles do matter somewhat for wings, but for the most part you can do whatever you want and the air will mostly push itself out of the way pretty effectively.
I doubt the amount of pressure building up in the bumper really does much to slow down the car — once it gets to a high enough pressure, it may as well be a solid mass, the same as blocking it off to prevent air entering — but if it does direct air into the void behind the car, then it could be helpful. Either way though there's no way to say without data... or at least some CFD.