Why Spa success doesn't guarantee Monza magic

Like birds of a feather, the Spa-Francorchamps and Monza circuits often flock together. The two are neatly aligned in the Formula 1 calendar, and form the last leg of European races ahead of the final set of flyaway rounds.

Both Spa and Monza are fast and sprawling circuits, winding through legions of trees on either side of the respective circuits. And when it comes to developing the right package to maraud the straights for lap time, Formula 1 teams would usually group the two tracks together.

But, contrary to popular belief, they're very different. Just as twin siblings have different personalities, the two circuits require different approaches to their aerodynamic configurations.

It's probably fair to describe Spa as the lowest-downforce variant of a 'regular' aero package, while Ferrari's sporting director Laurent Mekies describes the Monza approach as a "bespoke" arrangement.

"We all know Monza is a very special track," he says. "When we think about Monza, we think about things that are one of a kind and completely different compared to what we do elsewhere. It's different for aero, it's different for engines, it's different for brakes and different for car set-up as well. Because of all of this, it is the only track where we have a specific package."

Spa's requirements are much more mixed; while the run from La Source to Les Combes entices drivers to enjoy a series of challenging corners at full-throttle, there's a much larger percentage of corners on the lap, and those include a selection of slow-to-medium-speed corners that require some degree of downforce to navigate properly. That includes the Rivage hairpin after Les Combes, along with Fagnes and Stavelot - in other words, the majority of sector two.

When comparing Mercedes and Ferrari over the 2019 Belgian Grand Prix weekend, the disparity between the sectors was plain to see. Ferrari's low-drag SF90 was brutally quick in sectors one and three, especially in qualifying trim, but Lewis Hamilton's late-race hunt for victory was built on his colossal advantage in the second sector - he regularly found over a second's grace over eventual winner Charles Leclerc between Les Combes and Blanchimont.

In comparison, the sectors at Monza don't require quite as much compromise. Sure, sector two has the Lesmo corners, which present a lower-speed challenge, but there's a lot more time to be made through extracting a car's higher velocity on the straights.

Aerodynamically, then, Spa requires a lot more nuance compared to a Monza-grade aero package.

But not all teams can afford to build a fully-bespoke package. As one of the most moneyed outfits on the grid, Ferrari can afford to develop a great deal of Monza-specific aerodynamics, and it's almost obliged to do so - the pressure of racing on home turf is so substantial. For a midfield team, the amount of resource it can dedicate to one race is significantly reduced, so there's usually more similarities to the Belgium spec.

"There'll be some extra or some alternative parts available for Monza," explains Toro Rosso technical director Jody Egginton, "that might not bring performance [at Spa]. Spa and Monza have requirements regarding aero set-up in terms of efficiency but some other aspects with the car [at Spa] can be quite different to how you set up at Monza.

"Generally, for argument's sake, if we're struggling with stability [at Spa], it's something we have to get on top of for Monza" Jody Egginton

"In general, you can carry a lot more aero balance at Spa compared to Monza. You need a front wing flap that's optimised around those flap angles and that might not be the same for a wing that you run at Monza. Everyone's got their decisions to make on rear wing - we'll have options available and at Monza we'll see where we are.

"Then another aspect of the set-up is the mechanical difference, but you'll see some difference in aero package across the two events. We can group them together in many aspects, but we'll have options available [at Monza] so we're in the ballpark."

Toro Rosso's performance at Spa was strong, and both Daniil Kvyat and Pierre Gasly pocketed points finishes to keep the team holding onto fifth place in the constructors' championship. Despite the different requirements for aero stability between the two venues, Egginton believes that a strong Spa performance for the team is a good bellwether of how Monza should play out.

"Generally, for argument's sake, if we're struggling with stability [at Spa], it's something we have to get on top of for Monza," he adds. "We can't let that carry over. But to be honest, we don't anticipate that because mechanically the car has followed a reasonably logical set-up direction this year so far. We don't anticipate suddenly having a curveball thrown in."

Haas struggled with performance at Spa, and Gunther Steiner intimated after the race that the VF-19 had proven to be draggier than expected. Although Spa is a little more of a compromise as more downforce is needed, Kevin Magnussen suggests that Monza is a little more straightforward when it comes to set-up.

"Spa is very efficiency-sensitive," says Magnussen. "You need to be really efficient with your car because you need downforce a lot and you need low drag a lot. So around [Monza] you need downforce a little less, it's not as sensitive like Spa is.

"[It's a] little bit easier to set the car up in one direction, whereas Spa you need both. In the past we've seen many times teams have one high-downforce car and one low-downforce car, and they have similar pace just very different characteristics across a lap. Around [Monza] it's a little bit more one-sided, a little more simple."

Williams is expected to run in largely the same spec as at Spa, as it has not got the resources to develop a full-fat, low-downforce package. With its FW42 having been described as 'draggy" over the Spa weekend by both George Russell and Robert Kubica, a repeat of that performance at Monza seems inevitable.

That's not to say that a draggier package can't perform, and Jenson Button's curious decision to run a full barn-door rear wing in 2010 (below) almost paid off. McLaren was aiming to slice off the drag on the straights with the controversial F-duct rather than a skinny wing and consequently benefit from being quicker in the corners - although Button was consistently 10km/h down on eventual winner Fernando Alonso's Ferrari through the speed trap.

The simplistic idea of just trimming off drag isn't quite enough to perform at the Italian Grand Prix, and there's a lot of processes that each team must go through to develop their aerodynamics to suit the full circuit.

A novel solution once appeared at Monza during 2002, when F3000 driver Antonio Pizzonia raced to second with his top wing element turned upside down

In a modern F1 team, lap time simulation software is used prominently to outline and guide engineers towards a design solution. By creating a virtual mathematical model of a car, the engineers can play about with settings iteratively to find the best theoretical lap time. Once that has been found, they hand that to the aerodynamicists to turn theory into reality.

Enrico Cardile, Ferrari's head of aerodynamic development, explains the contemporary procedure to build the right low-drag package: "[At Monza] the sensitivity of the lap time to drag is 60% higher than the season average, while the load sensitivity is in the ballpark with the rest of the season. So, from there, we need to set a dedicated programme to get rid of drag efficiently while keeping in touch all the other characteristics of the car.

"To simplify the problem, we can divide the process for the Monza programme to be tackled in three different steps. The first is to reduce drag. We work on the less efficient components of the car, so the rear wing is completely redesigned, working on the shape of the profile, the incidence of the elements, the shape of the mainplane, and the flaps. Finally, we remove the winglets at the end of the engine cover fin.

"Once we are happy with the rear wing, the second step is to check the diffuser functionality. Because in unloading the rear wing, we are reducing its border with the diffuser, so we must be sure that we keep the diffuser working in any position, especially with very low rear ride height that's typical on a very high-speed circuit.

"The final [step] is dedicated to the front wing and after we reduce the rear half of the car, usually the front wing is too powerful. It means that the car balance would be too much on the front axle, even with the lowest flap angle allowed by the geometry. With the regulations we've worked mainly with the last two elements of the front wing.

"When we are happy with the package, we move to the simulator to check the performance and look for any further refinements needed."

There's also aero set-up work to be done at the track, too. Wing angles are adjustable, and if a driver finds that there's too little stability in the corners, or that the straight-line performance is too poor, then there's something that the teams can do.

A novel solution once appeared at Monza during 2002, when Formula 3000 driver Antonio Pizzonia raced to second with his top wing element turned upside down, which gave him a big boost on the straights. Although he struggled in the corners and was ultimately disqualified anyway, having the right set-up can make or break a race - just as long as it's legal.

Take too much downforce off, however, and the lap time will increase as the drivers have to fight with the car to navigate their way through the corners. There must be a balance.

But there's more to F1 than just aerodynamics. Monza is also hugely dependent on engine power, and Enzo Ferrari's spurious claim that 'aerodynamics were for people who couldn't design engines' was probably conveyed with this circuit in mind.

Although an F1 engine would struggle to send a tank down the main straight at 200mph, the reverse is also true, in that a full Monza-spec car would be nowhere without a powerful engine in the back. Although Mekies argues that Spa is more power-sensitive in other areas, the length of the lap compared to Monza brings its average speed down - and so, it's more prudent not to run the engine quite to the same level in Belgium.

Today, the 'Temple of Speed' requires a very different approach to the manner in which it was tackled in the past

"Full throttle is around 75% of the lap [at Monza]," Mekies explains. "The season average is around 60%, so that's a huge step and makes you realise how specific the work is going to be. The average speed around the lap is 260km/h [162mph], and there are many high-speed corners - the Parabolica, Ascari - [which] makes it the highest average speed of the year compared to the season average of 220km/h [137mph], nearly 15-20% up.

"It's the highest power effect of the year, which means you gain 10bhp on your engines and that's two tenths in your pockets. Strictly speaking, Spa is higher than that, but obviously Spa is 7km so that gives different numbers.

"Conveniently, a lot of people - us included - use it to bring their third and last power unit [to be used during the season]. Obviously, the engine performance will drop with mileage so you want a fresher engine in the highest power effect of the year."

In the days when the engines were as disposable as a paper cup, teams could bring their strongest powerplants to Hockenheim (its old configuration) and Monza. In the 1997 season (pictured above), the top eight spots on the grid were locked out by Renault, Peugeot and Mercedes runners - with some of the peakiest engines on the grid. Meanwhile, the Ferraris were mired in the midfield, while the V8 runners were relegated to the final two rows.

With fewer engine suppliers today, all offering relatively similar power levels, such extreme splits rarely occur, especially where gearing is homogeneous across the calendar. Although eighth-gear ratios are often based on being used at Monza - and at Mexico City, which offers the highest speeds on the calendar thanks to its reduced air density - they're all rather similar.

Today, the 'Temple of Speed' requires a very different approach to the manner in which it was tackled in the past. Special engines are out of the question, and tools like the F-duct are no longer allowed in the regulations. Instead, the key ingredients to succeeding at Monza include a low-drag car, but with enough downforce for the corners, and turning the engine up as far as you dare.

And if it's an all-or-nothing qualifying lap, get a tow.