A race car uses the air to push itself into the ground. Wings, a flat floor and a diffuser generate a downward force that increases tyre grip without adding real weight.
The key property, and the one that explains nearly everything else: that force grows with the square of speed. Double the speed, four times the downforce.
Two practical consequences follow:
And one dangerous consequence: if you lift mid-fast-corner, you lose speed, and losing speed loses downforce, and losing downforce loses grip — exactly while you're turning. That's why lifting in a quick corner is one of the few things that causes serious accidents.
Everything that generates downforce also generates resistance to moving forward. There's no way round it: it's the same air.
So every point of wing is an exchange:
The right question isn't how much grip you want, but how much time you spend in fast corners versus on the straights at that particular track.
| Track profile | Wing | Example |
|---|---|---|
| Very long straights, few corners | Minimum | Monza |
| Long straight plus a twisty section | Low-medium | Paul Ricard, Fuji |
| Balanced | Medium | Spa, Suzuka |
| Twisty, medium and slow corners | High | Imola, Brands Hatch |
| Lots of linked fast corners | High | Road Atlanta, Watkins Glen |
| Wet | Always high | Anywhere |
Direct method: do five laps with two points more and five with two points less, and compare sector times, not the overall lap. You'll see exactly where you gain and where you lose, and you can decide with data instead of feel.
Watch out for one classic trap: if you're going to race in traffic, a bit more wing pays, because behind another car you lose downforce and need the margin.
On most cars only the rear wing is adjustable, but the balance can be moved indirectly:
An idea that helps you decide: aero balance mainly matters at high speed. If the car is balanced in slow corners but understeers in the fast ones, don't touch bars or springs — look at aerodynamics.
These are two sides of the same phenomenon.
Tucked in behind another car on a straight, you meet less resistance and gain top speed. It's the overtaking tool at tracks with long straights, and it explains why at some circuits it pays not to lead on the last lap.
In corners, the car ahead leaves turbulent air. Your front wing receives disturbed flow, generates less downforce and the car understeers. The faster the corner, the worse it is.
How to live with it:
To carry on with the mechanical side, next is suspension, which decides how the car behaves once the aerodynamics stop helping.
On the straights, always. Over a full lap it depends: if the track has plenty of fast corners, what you gain there more than covers what you lose down the straight.
Because it grows with the square of speed. At 80 km/h the wing produces almost nothing; at 200 it produces a great deal. In slow corners grip comes from the tyres and the suspension, not the wing.
The turbulent flow a car leaves behind it. Whoever follows receives disturbed air, loses front downforce and understeers. That's why it's hard to follow closely through fast corners.
A great deal, on cars with a flat floor or diffuser. Lowering the car usually increases downforce, but if it bottoms out that downforce disappears instantly — the worst thing that can happen in a fast corner.
What it is, why it rotates the car, how to practise it and the mistakes that end in a spin.
Read →What each click does, how it shows up at the rear axle and how to find your value.
Read →What each parameter does, what order to touch them in and how to spot clipping.
Read →Two points up and two down, five laps each. It shows up sooner than you'd think.
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