i always see cars on here with big holes drilled out across the rear bumpers! do they serve a purpose or what??

 

its called a diffuser. it is supposed to help with air flow on race cars.

 

thats what i figured, would it really be functional on a daily driven vehicle?

 

NO, and it looks like ****! I want some of those guys to talk to an aerodynamicist...

 

Air is tramp in the rear bumper and that creates drag. Cutting holes into the bumper allow the air to vent out.

For daily use on the city I see no purpose. For highway, in theory you should be getting MPG.

If you want a rear diffuser look into these type.

 

it works like a diffuser, but not really. it's more of like a parachute effect. the holes well help eliminate the parchute effect your bumper gets when going at speed. for a DD, no purpose but to look tacky.

 

Below is an aftermarket diffuser for A Ferrari F430.



Without getting into the flow properties; our bumpers are a parachute. What the guys are trying to do is limit the amount of captured air at high speed. There are better way to achieve the same end result. Honda kind of did this for us…

 

...now that's funny! Same post; three people. ;-)

 

That's because we have helpful people here!

 

sometimes

 

True...

 

"Speed Holes" do nothing for a street car. I'd even question them on some DE or grassroots race cars too.

 

LOL speed holes!

<3 Toad.

As mentioned the aerodynamics are laid out stock... kinda, well areo does different things at different speeds.

Saying since a ferrari has one my hatch should is silly. Where is the wind tunnel testing? I've not seen ONE that is. If anything it's probably worse slapping random parts on messing with Hondas work.

While i've heard some people cutting the holes help for drag racing, I doubt it and can't say I've seen any proof of it.

Sadly there really is no market for areo products with hondas and it' a darn shame.

 

http://cgi.ebay.com/ebaymotors/Golde...Q5fAccessories

http://www.goldeneaglemfg.com/index....ex&cPath=79_92

 

at first i thought that was a joke.

 

^ haha, so did i! apparently its pretty popular of a product for such a quality company to produce them. hmmm....idk. i thought that knowing ebay "body kits" it would have been some no name thing, but golden eagle? of all companies to offer "speed holes" lol.

 

I don’t want to generalize, but most naming conventions are more interpretation than factual…

Equation: Holes + Bumper = Diffuser

Correct answer should be: Holes in Bumper

I've yet to read including text books that a hole could be construed as a diffuser! I call it misrepresentation!!

 

dictionary.com says

dif⋅fus⋅er   /dɪˈfyuzər/ Show Spelled Pronunciation [di-fyoo-zer] Show IPA Pronunciation

–noun 1. a person or thing that diffuses.
2. (in various machines or mechanical systems, as centrifugal pumps or compressors) a device for utilizing part of the kinetic energy of a fluid passing through a machine by gradually increasing the cross-sectional area of the channel or chamber through which it flows so as to decrease its speed and increase its pressure.
3. (in a lighting fixture) any of a variety of translucent materials for filtering glare from the light source.
4. a pierced plate or similar device for distributing compressed air for aeration of sewage.

 

dictionary.com says

dif⋅fus⋅er   /dɪˈfyuzər/ Show Spelled Pronunciation [di-fyoo-zer] Show IPA Pronunciation

–noun 1. a person or thing that diffuses.
2. (in various machines or mechanical systems, as centrifugal pumps or compressors) a device for utilizing part of the kinetic energy of a fluid passing through a machine by gradually increasing the cross-sectional area of the channel or chamber through which it flows so as to decrease its speed and increase its pressure.
3. (in a lighting fixture) any of a variety of translucent materials for filtering glare from the light source.
4. a pierced plate or similar device for distributing compressed air for aeration of sewage.

also says

dif·fus·er (dĭ-fyōō'zər) Pronunciation Key
n.
One that diffuses, as:
A light fixture, such as a frosted globe, that spreads light evenly.
A medium that scatters light, used in photography to soften shadows.
A device, such as a cone or baffle, placed in front of a loudspeaker diaphragm to diffuse the sound waves.
A flow passage in a wind tunnel that decelerates a stream of gas or liquid from a high to a low velocity.

 

By the time your done you'll have this

 

not a fan of em but i love these

 

What button do I press to transform that thing back into a civic!

 

Sorry; I should have clarified more!

Regarding vehicle under tray…

 

https://honda-tech.com/forums/performance-45/ac-bumper-diffuser-2281146/

 

almost like it'll be easier to remove the rear bumper cover