China has been on the Formula 1 calendar since 2004 and has quickly become one of the more interesting races of the year, with changeable weather and tricky tyre degradation it has produced some memorable races, including this year when Daniel Ricciardo carved his way through the field to take the win.
With the incredibly long back straight and more than a few sweeping corners the Shanghai International Circuit calls for a very balanced setup, but will reward good traction and a responsive car.
We have taken a turn out of the front wing and two from the rear wing to reduce drag and help us down the huge back straight, however we can't do away with it all together. We need good front wing downforce to get the car turned in, especially with the very tricky turn 1 and 2 section that can be very harsh on tyres and demanding on your whole setup.
As for the rear downforce, we have taken away as much as we can while maintaining the downforce needed for the turn 8/9 section as well as the acceleration through turn 12/13.
Locking up the differentials is great for traction, but bad for tyre wear. Since those things are already in a fine balance around the Shanghai circuit we haven't played with this too much. The slightly more locked on throttle differential just gives us a boost in traction through turn 12/13 and on to the back straight, while leaving the off throttle differential alone gives us a good compromise between turn-in and stability.
Suspension geometry is all about how the wheels are aligned with the body of the car. Camber is how they sit vertically in relation to the rest of the car. All F1 cars are set up with negative camber, meaning the top of the tyre is closer to the body than the bottom is. This makes the front of the car more responsive and provides better grip during corners as the outside tyre gets loaded up. What camber does do though is scrub speed in a straight line, so around China we are taking some of the camber away to help reduce rolling resistance.
Toe is all about the horizontal alignment of the tyres to the body of the car. Front wheels are set to toe out, meaning the front of the tyre is further away from the body than the rear is. this makes it more responsive on turn in, but again it comes at the cost of straight line speed, so we are taking a little away. The rear tyres are set to toe in, and by adding slightly to that we help stability and straight line speed.
We have a relatively stiffly sprung car around Shanghai to help us reduce weight roll and improve aerodynamic stability. The surface is relatively smooth and we don't need to take a lot of kerb either, allowing us to keep stiffer front and rear suspension. However, it does add to tyre wear as we aren't allowing the weight to move under braking and acceleration.
We get some of that tyre wear back by softening the anti-roll bars, which helps the weight move laterally. With only one high speed switch of direction at turn 7 & 8 we don't need to worry too much about the roll there, and by having the rear a little stiffer you can get the power down more evenly in the exit of the corners.
Finally the ride height, which is where we get some speed back. The smooth surface and lack of kerb-riding means we can drop the ride height significantly. With a 4-4 setting we leave ourselves some margin to take the kerb at the hairpin if we are making a late lunge to overtake, or at turn 16 to get a better drive down the pit straight.
The brake pressure is all about stopping distance. The higher the pressure the more stopping power you have, but the more likely you are to lock up. With two big braking zones into turn 6 and turn 14 we want a higher pressure, and fortunately there are very few corners with a tricky braking zone that could result in a lock up. Stopping for turn 9 is always a little tough if you get your line wrong through 8, but other than that every other braking point is very simple.
To counter some of the work we have done to reduce the effect of suspension geometry on top speed the car is not as responsive as we'd like, which is where tyre pressure comes in. An increased tyre pressure creates a superior contact patch when cornering, extremely helpful in turn 7 and 8, as well as the difficult turn 1/2 combination. It also reduces rolling resistance, which makes up for a slight loss of traction from higher pressured rear tyres.
Moving the ballast rearward increases traction and oversteer. We'd like the traction, but the car is extremely well-balanced thanks to the rest of our setup, so it's best to leave the weight ballast in the middle at 6.
That's out set up for the Chinese Grand Prix. It is not going to give you extreme top speed, but it will get you around the rest of the lap in a hurry and is a very good base line to tinker to your specific driving style. See you on the time sheets!
Chinese Grand Prix Wet Setup
Front Wing: 6
Rear Wing: 8
On Throttle: 50%
Off Throttle: 70%
Front Camber: -2.80
Rear Camber: -1.30
Front Toe: 0.08
Rear Toe: 0.32
Front Suspension: 5
Rear Suspension: 4
Front Anti-Roll Bar: 8
Rear Anti-Roll Bar: 6
Front Ride Height: 5
Rear Ride Height: 5
Brake Pressure: 88%
Front Brake Bias: 55%
Front Tyre Pressure: 23.0 psi
Rear Tyre Pressure: 21.1 psi