Rear bumper vent?

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product1620
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Rear bumper vent?

Post by product1620 »

Well, the last couple days iv'e been working on the fiero and trying some things out. I'm doing a hood vent; in fact ive already cut it out, I just need to finish sanding it. While I was working on the hood I kept thinking about other problem areas for trapt air. One that really stuck out was the rear bumper. I know of some drag racers who vent their rear bumper so as to allow the air that gets trapt from underneath the car to be vented. so what I did today was I took a two inch drill bit (the circluar ones used for makeing door knob holes) and put three holes on each side of the lower bumper near the tag. My question is do you think this will do a sufficient job of venting the traped air???

My camara's battery was dead today, so I will try to get pics tomowrow.
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Post by donk_316 »

ohhhh i gotta see this...
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Post by product1620 »

Is that sarcasm I sense??? :la:
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Post by Shaun41178(2) »

what drag racers do this? You talking of civics? I think I know what you are talking about but I want to see whats really on your mind.
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Re: Rear bumper vent?

Post by MNFatz »

product1620 wrote:Well, the last couple days iv'e been working on the fiero and trying some things out. I'm doing a hood vent; in fact ive already cut it out, I just need to finish sanding it. While I was working on the hood I kept thinking about other problem areas for trapt air. One that really stuck out was the rear bumper. I know of some drag racers who vent their rear bumper so as to allow the air that gets trapt from underneath the car to be vented. so what I did today was I took a two inch drill bit (the circluar ones used for makeing door knob holes) and put three holes on each side of the lower bumper near the tag. My question is do you think this will do a sufficient job of venting the traped air???

My camara's battery was dead today, so I will try to get pics tomowrow.
Let me guess. Fast and the Furious?

(if not, the license plate lite mounting holes I'm sure do the job...)
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Post by product1620 »

Shaun41178(2) wrote:what drag racers do this? You talking of civics? I think I know what you are talking about but I want to see whats really on your mind.
I'll try and get some pics tomowrow. I'm not sure of the exact racers, but I know ive seen this done to some of the street/strip cars.
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Post by product1620 »

Let me guess. Fast and the Furious?
Umm, no. I, unlike a lot of people, don't take those movies seriously, and certainly don't use them as a reference for performance tips. :angel:
(if not, the license plate lite mounting holes I'm sure do the job...)
Those are like what a half inch by and inch, I don't think that is going to vent too well.
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Post by slow'n'steady »

a while ago when i had my neon, i was on neons.org a lot and i remember reading about this EXACT same thing. the guy cut 6 2" holes (3 on each side) then laid wire mesh behind. looked kinda dumb to me but he reported something like 12-16 more miles per tank of gas.
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Post by Aaron »

Personally I'd take a sheet of fiberglass and block off the bottomside so air can't get above it, but I guess your way takes away weight instead of adding it...
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Post by product1620 »

slow'n'steady wrote:a while ago when i had my neon, i was on neons.org a lot and i remember reading about this EXACT same thing. the guy cut 6 2" holes (3 on each side) then laid wire mesh behind. looked kinda dumb to me but he reported something like 12-16 more miles per tank of gas.
I think it looks decent, but it dosen't really matter to me anyway, cause i'm more into function than form (at least when it comes to cars :la: )
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Post by Aaron »

Then why not take the bumper off?
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Post by product1620 »

Aaron wrote:Personally I'd take a sheet of fiberglass and block off the bottomside so air can't get above it, but I guess your way takes away weight instead of adding it...
That is my main reason for doing it this way, and plus it simplifies the whole thing. The weight savings is also the reason I chose to just cut out the hood vent rather than using and add on peice.
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Post by product1620 »

Aaron wrote:Then why not take the bumper off?
Then where would I mount the license plate? :la:

Honestly, I don't want it to look like complete trash, but somthing as small as bumper vents dosen't bother me.
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Post by slow'n'steady »

well, then why not form and function? i just think the six Os would look goofy, ESPESCIALLY on a fiero!! maybe a couple like 2" X 6" rectangular holes or something? i just think if you wanna do it, it would be pretty easy to make it functional, yet not obvious that you just took a hole cutter to the bumper... i wish i could find the pics of the neon that did it, then you;d see what i was talkin about.
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Post by The Dark Side of Will »

slow'n'steady wrote:a while ago when i had my neon, i was on neons.org a lot and i remember reading about this EXACT same thing. the guy cut 6 2" holes (3 on each side) then laid wire mesh behind. looked kinda dumb to me but he reported something like 12-16 more miles per tank of gas.
Interesting... How did he arrive at this conclusion? IOW... did he record his data and compare fillups to the odometer, or did he just use the ass-o-meter? That's an extra 1.5 mpg or so, guessing the Neon's tank to be about 10 gallons.
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Post by whipped »

speed holes!
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Post by Pyrthian »

Shaun41178(2) wrote:what drag racers do this? You talking of civics? I think I know what you are talking about but I want to see whats really on your mind.
exactly. real racers use belly pans to keep the air from being trapped in the first place.
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Post by slow'n'steady »

The Dark Side of Will wrote:
slow'n'steady wrote:a while ago when i had my neon, i was on neons.org a lot and i remember reading about this EXACT same thing. the guy cut 6 2" holes (3 on each side) then laid wire mesh behind. looked kinda dumb to me but he reported something like 12-16 more miles per tank of gas.
Interesting... How did he arrive at this conclusion? IOW... did he record his data and compare fillups to the odometer, or did he just use the ass-o-meter? That's an extra 1.5 mpg or so, guessing the Neon's tank to be about 10 gallons.
well i dont remember exactly how it all wwent down, but somethng like he was visiting a friend in another state, and recorded the odo/fuel on the way down there, ended up cutting the holes while there, then took the same route back recording odo/fuel and ended up something like 10-13 further or somethin like that.... its on the neons.org website, i looked for a few minutes but gave up, it was prolly like a year ago when i read it.
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Post by Kohburn »

sounds like too small a change to base anything on - especially with a reverse trip with uncontrolled conditions
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Post by Pyrthian »

Kohburn wrote:sounds like too small a change to base anything on - especially with a reverse trip with uncontrolled conditions
it was uphill, both ways....
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