Aerodynamics In Car Tuning

[noaim]

Thought this would be helpful:

Car aerodynamics deals with all processes which are observed as air flows through and around a vehicle.

Air resistance W = cw . A v2. Q/2

where cw = drag coefficient,

A cross-sectional area,

v driving speed

Q air density.

The factors to be influenced by the vehicle manufacturer are the drag coefficient cw as a measure of the aerodynamic quality of the vehicle shape, and the projected vehicle cross-sectional area A.

Attempts to reduce the cw value by adding spoilers, underbody panels, etc. are not practical, since their effect depends upon the aerodynamic characteristics of the basic vehicle body. These types of modifications in optimized form are standard features of modern vehicle design. This means that the fitting of supplementary devices to further improve the cw value and the axle lifting-force coefficient can only result in very minor improvements. Often, such modifications result in the impairment of the vehicle's day-to-day capabilities due to reduced overhang angle or reduced ground clearance. In other words, such add-on parts serve more for improving the vehicle's appearance than for improving its performance.

The cw value can be influenced by individual aerodynamic or design measures. Airflow through the vehicle as well as roof-mounted fixtures will always increase the cw value. Examples (- = better, + = worse).

Effect of ------------ delta cw in %

Lowering vehicle height by 30 mm.----------- approx. -5

Smooth wheel covers ----------- -1...-3

Wide tires ------------ +2...+4

Windows flush with exterior ------ approx. -1

Sealing body gaps --- -2...-5

Underbody panels---- -1...-7

Concealed headlamps ------------ +3...+10

Outside rearview mirrors -------- +2...+5

Airflow through radiator and engine compartment ------ +4...+14

Brake cooling devices ----------- +2...+5

Interior ventilation --- approx. +1

Open windows -------- approx. +5

Open sunroof --------- approx. +2

Roof-mounted surfboard rack --- approx. +40

Effect of windshield slope on the cw value

(- = better, + = worse)

Windshield---cw------ delta cw in %

slope

50 deg.--- 0.345---- --

55 deg.--- 0.342---- -0.8

65 deg.--- 0.34---- -1.4

40 deg.--- 0.349---- +1.1

30 deg.--- 0.349---- +1.1

00 deg.--- 0.369---- +7

From: http://www.tuninglinx.com

[sharkster]

interestin info nuaim...a link wud b nice

[miniace]

Somebody please show this to local fibre body kit makers ,especially Dumi##a !!

[JwesT]

Drag Coefficients of cars

2005 BMW 3 series - 0.31

2005 BMW 6 series - 0.30

2005 BMW 5 series - 0.29

2005 Porsche 911 - 0.28

2005 Merc SL500 - 0.29

2005 Merc CL500 - 0.28

2005 Nissan 350Z - 0.30

2005 Acura NSX - 0.30

2005 Merc S500 - 0.27

2004 Aston Martin Vanquish - 0.35

2004 Aston Martin DB9 - 0.34

Ferrari F360 Modena - 0.33

Ferrari F430 - 0.33

Source:- vBulletin v3.0.6, Copyright 2000 - 2005, Jelson Enterprises Ltd

Neither Ferrari nor Aston Martin make good designs huh?

[dillongt]

LOVELY INFO MACHAN....THANX.... Index to Coefficient of Drag for Many Vehicles

Plus Index to Horsepower vs Speed Curves CLICK HERE 4 MORE INFO