s14 race aero

Forum for Nissan wheel fitment, tire selection, suspension setup and brake discussions.
chmercer
Posts: 2810
Joined: Sun Mar 09, 2003 5:04 pm

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does anyone have any pics of the underbody of any jgtc s14's or anything similar? i am looking for ideas on making an undertray and diffusers. if anyone has any pics or anything that might help, please post. thanks!

(ps, didnt really know where to put this, usually smart ppl in the susp. forum)


Nismo_Freak
Posts: 10314
Joined: Wed Jul 24, 2002 10:42 pm
Car: 89 Nissan 240SX

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IBspeedbump

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SmithSR
Posts: 5021
Joined: Sun Feb 23, 2003 3:16 pm
Car: 240sx

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http://www.jgtc.net/race/whats/04t_regu_en.htm

Flat bottom:

"It is obligatory to install a flat bottom over the entire length of the car as viewed from underneath excluding wheel the housing and outer rear view mirrors. Between the front and rear wheel centerlines, the underbody of the car shall be securely fitted to a solid structure which is flat, impervious and rigid under all circumstances. The flat bottom shall not have an aerodynamic effect under any circumstance. No air stream may pass between the floor of the ****pit and the flat bottom. It is permitted to have a radius of maximum 25mm upwardly at the perimetric edge of the flat bottom."

From reading that and other info on that page, it would seem that, excluding a rear diffuser, there is to be nothing under the car except a flat plate as stated above. Check the part on "Aerodynamic Device"

Nismo_Freak
Posts: 10314
Joined: Wed Jul 24, 2002 10:42 pm
Car: 89 Nissan 240SX

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The idea would be to accelerate under body flow... so as to create a vacuum.

Problem is... the car isn't low enough nor will it travel fast enough to substantuate making underbody paneling.

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SmithSR
Posts: 5021
Joined: Sun Feb 23, 2003 3:16 pm
Car: 240sx

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We have a winner!!

Nismo_Freak
Posts: 10314
Joined: Wed Jul 24, 2002 10:42 pm
Car: 89 Nissan 240SX

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W00t... now mail me a set of tires!

chmercer
Posts: 2810
Joined: Sun Mar 09, 2003 5:04 pm

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Well, I can get a hold of some aluminum plate for next to nothing, and was wanting to play around with it. "if" (big if) i made a 1 piece undertray, i wouldnt be trying to create a low pressure area to such a great extent that it would cause suction, but wouldnt it decrease the pressure at least minimally, since i would be blocking off a good deal of exposed components, reducing turbulence?

it would probably not make any downforce, but it would at the very least decrease lift a small amount, the way i see it. please explain if i am wrong?

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Exar-Kun
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Car: 2005 350Z
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it would decrease drag, but as far as lift..I would think without vanes it could actually increade lift, since a car has the shape of a wing..kinda..

but at least you'd decrease drag..I would think lift would increase much, if at all..-chet

chmercer
Posts: 2810
Joined: Sun Mar 09, 2003 5:04 pm

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well i mean i would put strakes on the diffuser in the back, not sure how the front would be done yet.

fluid dynamics is hard :(

Doogz
Posts: 667
Joined: Thu Mar 13, 2003 5:58 am
Car: '89 240sx coupe

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SmithSR wrote:No air stream may pass between the floor of the ****pit and the flat bottom.


You can't even say ****pit!!??


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