Welcome to The Briefing, where you can get a jumpstart on the Belgian Grand Prix with our guide to the key topics.

Every race weekend, we’ll speak to one of our engineers to discuss the key talking points ahead of the upcoming Grand Prix and simplify them so that you can dive straight into the action with a better idea of what to expect and what you should be looking out for.  

This week, powered by Google Cloud, we spoke to Jose Manuel López, who will walk us through a very different type of circuit from the one we visited last weekend in Hungary. Jose will explain why the Circuit de Spa-Francorchamps’s fast and flowing nature is so different to the tight and technical Hungaroring and what impact this will have on our weekend. He’ll also discuss the relevance of Spa’s new surface and how we’ll find the balance between drag and downforce.

Here’s what you need to know…

1. This circuit shares very few similarities with Hungary's track

Having Hungary and Belgium back-to-back is an interesting calendar choice, as the circuits are extremely different. That’s in our minds, and certainly in the drivers’ minds, because we’re coming from a track where the car is on the full high-downforce package that grips a lot and stops rapidly when you hit the brakes, to somewhere that requires way less drag.

Here at Spa-Francorchamps, the drivers are approaching corners at much higher speeds, with much less grip, compared to the Hungaroring. The car moves around more, there’s more rear-locking, front under-rotations, and sliding through the corners. The drivers will be thinking the MCL38 that felt great last week suddenly doesn’t feel so good anymore - and so it’s something we talk about in briefings and emphasise that this is a low-downforce package, and that has consequences.

An added difference this weekend – though quite predictable – is the much lower temperatures. What does that mean for the car? The bodywork will be tighter around the rear, which will help us recover some load. Tyres will suffer a little less with thermal degradation – although it will still be the dominating factor on Sunday if the temperatures are not too low. If they dip lower than the currently forecast 20°C, then we might see some graining, depending on which compound is fitted.

We have the C2, C3, C4 tyre allocation at Spa this weekend, the same as last year.

2. The circuit has been resurfaced and this poses questions

Much of the track was resurfaced in June and this is the big unknown. It's a huge amount. Something we haven’t seen often. Jeddah perhaps, and Turkey, where they water-blasted the surface from one season to the next and we picked-up four or five seconds. This is the dominating factor all of the teams will be keen to understand today. It has implications for tyre management and, as we’d expect Belgium to be a two-stop race, for tyre allocation. It could change the tyre models everybody works from, so it's a big topic to focus on.

Where are we going to gain lap time? The first and last corners have been resurfaced, as has the section down to Eau Rouge, at the top of the hill after the Kemmel Straight, and then from Turns 14-15.

So, potentially we’ll see traction gains out of the last and first corners. Performance in those two lower-speed turns is crucial. Before the resurfacing, speeds there were around 75-78km/h. Now? We’ll find out. We’ll also have potentially more grip at the top of the hill through the corners at Les Combes and the Hairpin. Turn 15 is flat in Qualifying but not in the race with a full fuel load, so that could be a little bit quicker as well.

3. Finding the correct balance between drag and downforce

We have a lower downforce rear wing available this weekend. It’s not exactly new – it was available at Silverstone – but it’s one we haven’t raced yet and so this is the first time we’re going to see it on track. And we also have a couple of beam wing options to try out with it.

It isn’t a circuit where we’d want to run with aero rakes because the length of the track means you get very few laps, and spending time in the garage removing rakes, reduces the lap count further – but we will be doing some rear wing filming and flo-vis.

Will we add downforce if it’s raining? It depends more on what we’re expecting on Sunday, rather than what’s happening on Friday and Saturday. At the moment, Sunday looks like the day more likely to be dry. With a dry track, lower drag is important, and you’ll simply attempt to do the best you can with what you have before then.

We ran more downforce last year, which was a mistake. Yes, it was faster for overall lap-time, and we qualified a bit better – but on Sunday in the Grand Prix, we were sitting ducks on the straights, and had to try a marginal strategy to get out of traffic. With more downforce and lower end-of-straight speed, you’re going to be overtaken and this is a problem. It’s good for lap-time, but having the fastest car for lap-time isn’t the optimum approach at Spa, you have to bias in favour of what’s going to happen in the race.

It’s very different to Hungary where, if there is any doubt, you bias in favour of Qualifying, because it’s a bit more difficult to overtake. In Spa, it’s all about Sunday, so that’s the weather forecast you have to take into account.

Finding that correct drag/downforce trade is a key topic for practice. Sectors 1 and 3 have high-drag sensitivity, whereas Sector 2 has high grip sensitivity. What we’ve also learned over the last few years is that traction out of the last chicane, and out of Turn 1 is extremely important too. Even if you have the correct drag level, if you lose ground to the car ahead because it has better traction, then they open the gap enough to make it very difficult to catch up before Turn 5.

With faster lap times and more grip, we need to understand what the best approach is. We’ll have a little bit of work to do at high fuel… though we’ll also be looking at the radar quite a lot too.

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