Wings/Aero
Wings are different than the other handling‐adjustment tools for several reasons. The magic of a wing is that it produces load on the tires – which translates to increased corner speed and in the case of very powerful cars, stronger acceleration off the corner without wheelspin – without a significant weight penalty. The downforce produced by the wing increases as vehicle speed (and therefore the speed of the air over the wing) increases, albeit with a concurrent increase in aerodynamic drag that slows the car’s straightaway speed.
Different wing designs have different lift/drag ratios, but in most racing classes today the aerodynamic design of the wing is set by the rules. What is adjustable is the angle of attack of the wing. The number shown is in reference to the horizontal. The higher the number, which is given in degrees, the steeper the angle of the wing relative to the airflow. Up to the point that the wing becomes aerodynamically stalled, as the angle of attack increases so does the level of down‐force, as well as the amount of drag, which slows straightaway speeds. (A stalled wing produces the worst of all possible worlds; downforce is greatly reduced and drag increases sharply.)
It is important to note that with properly adjusted wings, the speed lost on the straightaway due to drag is far exceeded by the beneficial effects of increased corner speeds. Not only does the car spend less time negotiating the corner, but the sharply increased speed at which the car enters the straightway means a shorter time from the exit of one corner to the entry of the next, even if terminal speed on the straightaway is decreased.
On some cars, other aerodynamic devices may be used instead of or in addition to wings. However the advantaged and disadvantages of them are similar to wings, although their aerodynamic efficiency (or the amount of downforce they produce per a given unit of drag) varies. They will be described more below:
Adjustments
Spoiler setting – A spoiler is an automotive aerodynamic device whose intended design function is to 'spoil' unfavorable air movement across a body of a vehicle in motion. A spoiler has a significant effect on the lift or downforce of a vehicle and its aerodynamic drag. The spoiler setting adjusts the angle of a spoiler of fixed size, with the downforce and drag increasing with increasing angles.
Wing setting – This adjust the angle of attack of the wing. Downforce and drag increase with increasing wing angle until the wing stalls, at which point the drag continues to increase but the downforce falls off (note stall is usually not a concern for the allowed adjustment range of the game).
Wicker height – The wicker or more accurately the wickerbill or Gurney flap is effectively a small spoiler attached to the trailing end of a wing to improve performance. Wickers can be changed rapidly to tune the aero of a wing, with larger wickers generally giving more downforce.
Wicker span – On front wings, it is common for wickers to not run the entire length of the wing. Obviously, as the span (or width) is reduced the effectiveness or downforce of the wicker will also be reduced, however the drag and turbulence created by the wicker is reduced. Because of the large impact of front end turbulence on the flow over the car and to the rear wing, a smaller/narrower does sometimes produce more overall downforce than a larger one.
Front dive planes – Dive planes are small plates or winglets attached to the side of the nose to increase front downforce. They look similar to the “dive planes” on submarines, thus the name.
Horiz wicker height – Explanation of this device/setting?
Horiz wicker span – Explanation of this device/setting?
Side wicker height - Explanation of this device/setting?
Ramps and extensions – Explanation of this device/setting?
Data
Front RH at speed – This is YOUR ESTIMATE of the front ride height at operation conditions used to calculate the front downforce and downforce to drag. How do you come up with a good estimate?
Rear RH at speed – This is YOUR ESTIMATE of the rear ride height at operation conditions used to calculate the front downforce and downforce to drag. How do you come up with a good estimate?
Front downforce – This is a calculated front downforce percentage based on your entered operating ride height estimates and the current wing/aero settings.
Downforce to drag – This is a calculated downforce to drag based on your entered operating ride height estimates and the current wing/aero settings. Higher values are better.
Tuning advice
Aerodynamics has a big impact on the performance and handling of a racecar, and can mask problems in other areas. Thus race engineers often talk in terms of mechanical grip, which is the cars handling without aero effects (which is dominate in slow speed corners), and aero grip, which is the cars handling with the full aero package at high speeds where the downforce tends to dominate the cars handling. It is because of this that is it often recommended that the optimum mechanical grip be established first with a balanced low downforce setup and THEN optimize the aero settings to provide the best performance for the track.
Aero tuning is all about trying to get as much downforce as possible for an acceptable amount of drag, and while providing the proper front to rear balance. Take a hard look at the track to help figure out the best approach. Downforce is king in high speed corners, it helps some in low speed corners with no need to worry about drag, but long straights are where low drag and low downforce pays off.
Front
Increasing the setting/angle: Increases the angle of attack and the level of front grip, especially at the higher‐speed sections, such as the braking zones at end of straights. Thus increasing the % front downforce value and reducing aero understeer or increasing oversteer. The compromise is an increase in drag, but a similar change to the rear wing will generally result in an even greater increase in drag. Adding dive planes and increasing the wicker height or width will have a similar result, but usually at a higher drag penalty. In general it is best to avoid large wicker settings with low wing settings, as this is less aerodynamically efficient than wickers which are proportional to the wing setting. Wicker changes have less impact than wing changes and are normally used for fine tuning, but they can improve wing efficiency and performance and have the real world advantage of allowing rapid adjustments in the pits.
Decreasing the setting/angle: Decreases the angle of attack and the level of front grip, especially at the higher‐speed sections, such as the braking zones at end of straights. Thus reducing the % front downforce value and reducing aero overersteer or increasing understeer and reducing drag.
Rear
Increasing the setting/angle: Increases the angle of attack will add grip and shift the balance to UNDERsteer. The compromise is that drag increases and straight‐line speeds will be lower. Note that the rear wing is normally much larger than the front wing and thus has a larger effect on drag. Also note that the same front and rear wind settings or changes rarely results in the same downforce or downforce change for the front and rear, this is because of the size and geometry differences of the wings along with the deferent heights and conditions that they operate in. Increasing the wicker height or rear spoiler angle will have a similar result, but usually at a higher drag penalty. In general it is best to avoid large wicker settings with low wing settings, as this is less aerodynamically efficient than wickers which are proportional to the wing setting. Wicker changes have less impact than wing changes and are normally used for fine tuning, but they can improve wing efficiency and performance and have the real world advantage of allowing rapid adjustments in the pits.
Reducing the setting/angle: Increases the angle of attack will reduce grip and shift the balance to OVERsteer.
The other aero settings generally impact the underbody or overbody airflow and have a less clear impact on the front to rear balance. Keep a close eye on the calculated front downforce and downforce to drag values when changing these setting to help guide you in the right direction. As a final note, in many cases low downforce and high downforce setups will produce equivalent lap times around a circuit. When this is the case, consider which setup is easier to drive or produces more consistent lap times and how they perform in traffic and passing situations.
Interactions
The ride height and rake have a big influence on the aerodynamic performance of the car. In addition, the increased load of downforce often requires increased tire pressure and stiffer springs and shocks to support and control them.