The Mexican Grand Prix returned to the Formula 1 calendar in 2015 after a 22 year absence and was quickly dominated by Mercedes thanks to its power-hungry nature. The long pit straight drains your battery, while the tight chicanes and winding esses require some precise braking and smooth steering. A good setup can greatly improve your ability to carry speed through the middle of the lap as well as transition from the super-slow stadium section onto the main straight. How should you set your car up?
Aerodynamics
Mexico requires a rather unbalanced aerodynamic setup. Drag is a killer for straight line speed, and given the massive pit straight we want to reduce it as much as possible. As such we go with a front wing angle of just 3. This isn't great for the turn in of the slower corners, but the performance is too good down the straight to ignore. The rear wing is set to 6, this is to provide rear stability to allow us to stay on the power through the middle sector and get the power down out of the stadium and onto the straight.
Transmission
The transmission part of the setup dictates how the power is deployed from the engine through the rear tyres and into the tarmac. A more locked on-throttle differential forces the rear wheels to rotate at the same rate, improving overall traction but at the cost of tyre wear. Wear can be extremely high around Mexico due to the fast esses and heavy braking zones into turn 1 and the stadium section. As a result we are locking the on-throttle differential only ever so slightly, and then unlocking the off-throttle to help with rotation into corners.
Suspension Geometry
Suspension geometry is all about how the tyres are aligned with the body of the car. Camber is their vertical alignment. F1 cars are always set with negative camber, meaning the top of the tyre is closer to the car than the bottom is. This helps with cornering grip, but adding more camber changes the contact patch with the tarmac and increases tyre wear while hurting straight line speed. We don't want any of that, so we are taking a click of camber off both the front and rear tyres.
Toe is the horizontal alignment of the tyres. Front tyres are set to toe out, meaning the leading edge is pointing away from the rest of the car. This helps with turn in but again reduces straight line efficiency. With the tight stadium section and several slow chicanes we want some turn-in, so we have left the front toe alone.
The rear tyres are set to toe in, with the leading edge pointing in to the car's body. By adding to it slightly, we have made the car more stable under acceleration.
Suspension
The suspension is vital for this track. Maximising your speed through the esses of the middle sector is vital to putting in a good lap time, and while an optimum one-lap suspension setup looks very different, for a race this is a well balanced suspension.
The 6-4 front-rear balance allows weight to transfer backwards under acceleration to aid traction, but prevents it lurching forward under braking too much. The anti-roll bars are similarly set to a firmer front, softer rear with a 7-5 setting. This keeps the front responsive while allowing the weight at the rear to slide laterally and maintain power through cornering.
Ride height is set to 3-4 to create a rake. What this does is make the car more responsive in cornering. It does mean you should be careful over the kerbs, but you don't need to take too many liberties with them here.
Brakes
The brakes are all about stopping power. Increasing brake pressure improves stopping distance, but it increases the chance of lockups. Mexico's primary overtaking point is turn 1 after the long straight, and getting stopped in good time is vital. The 85 percent setting is a good balance.
Brake bias is about which tyres do the majority of the stopping. The front tyres should do the majority of the braking, but by shifting the bias rearward to 57 percent you create a little oversteer to help get the car into the corners.
Tyres
We haven't changed the tyre pressures much. Increasing front tyre pressure would make the car more responsive under cornering but increase wear. We have a pretty good balance already so have let it be. With the rear tyres we have taken away some pressure, this increases the contact patch and overall traction, helping us accelerate away from corners.
Weight Distribution
The weight ballast is set to 8. This improves traction greatly and increases oversteer once again to finish off a good setup for a tricky track.
The Mexican Grand Prix can be hard to get right. Tyre wear is tough to manage, but this setup helps extend stints as long as you don't abuse the tyres into braking zones or light them up out of the last corner too much. It is well balanced between straight line speed and responsiveness, and can take a poor car up the grid well in career mode. See you on the timesheets!
Mexican Grand Prix Wet Lap Setup
Front Wing: 4
Rear Wing: 7
On Throttle: 65%
Off Throttle: 100%
Front Camber: -2.60
Rear Camber: -1.10
Front Toe: 0.06
Rear Toe: 0.23
Front Suspension: 6
Rear Suspension: 4
Front Anti-Roll Bar: 8
Rear Anti-Roll Bar: 5
Front Ride Height: 4
Rear Ride Height: 5
Brake Pressure: 90%
Front Brake Bias: 54%
Front Tyre Pressure: 23.0 psi
Rear Tyre Pressure: 21.1 psi
Ballast: 7