Could new start procedures prove Mercedes undoing?
Mercedes may have utterly dominated qualifying, finishing nearly a second ahead of Valtteri Bottas, their closest rival, but if Lewis Hamilton and Nico Rosberg learnt anything from Hungary it's that making a good start is the crucial factor to converting their relentless pace into victory.
Back in Budapest bad starts put both drivers on the back foot, and neither was able to fully recover, so both will be more determined than ever to get a good jump when the lights go out on Sunday. That, of course, will be easier said than done, what with the introduction of new start procedures for this race - a move that should make for much more unpredictable getways and could lead to the order being shuffled considerably by the first corner.
The main difference between this race and Hungary is that drivers now have to prepare the clutch settings for the start themselves, without the usual assistance from their race engineers. Naturally, the drivers have all been rigorously practising starts at the pit lane exit all weekend, but the grid area is situated on far less of a slope, so it's been far from ideal.
Overall the prevailing sense amongst the drivers heading into Sunday's race is that the new procedures are a step into the unknown - and no one has more to lose than those on the front row…
Ferrari looking to recover from dismal qualifying
The talk coming into Spa was of Sebastian Vettel's burgeoning title charge, and whether the German could keep the pressure on Mercedes after his brilliant victory in Hungary.
However, Ferrari's hopes of an amazing reversal in the championship standings took a blow on Saturday when Vettel could manage no better than ninth in an extraordinarily tight top-ten qualifying shootout. Team mate Kimi Raikkonen fared even worse, a loss of drive in Q2 leaving him 14th on the grid.
But all is not lost for the Scuderia, who have shown decent straight-line speed all weekend - a factor that will be crucial as Vettel and Raikkonen battle to make their way up the order against Mercedes-powered cars.
"Tomorrow we should have decent pace and pretty good straight line speed to turn things around," said a bullish Vettel after qualifying. "We have a good car and a strong package for the race. There's a lot to be done tomorrow, it's a long race, the start and first turn will be interesting and there could be some rain at some point. There's nothing wrong so we're expecting progress."
The question is, how much progress will Vettel make, and will he still fancy his chances of causing a title upset come Sunday evening?
Two-stop strategies to dominate - but tyre worries rumble on for Rosberg
It's not been the easiest of weekend's for Pirelli, what with Nico Rosberg's dramatic tyre blowout during FP2 on Friday. After a long investigation the Italian firm announced on Saturday morning that they'd found no structural integrity issue with the tyre, and that an external cut had probably caused the failure - but heading into Sunday's race, Rosberg remains concerned.
"The problem is that we don't really understand it," he said. "There are theories but there's no real evidence so that's a bit worrying for sure. But we're keeping a very close eye on it and we've done some measures to make sure it doesn't happen again. So we've done the best we can and just hope it all works out and stays together."
Barring further problems, a two-stop strategy looks the best way to tackle the 44-lap race. The soft compound - which has proved to be around 1.4/1.5 seconds per lap faster than the medium - is the tyre that the drivers will be aiming to spend the most time on, in which case they'd start of softs, collect a further set around lap 15 and then switch to mediums around lap 30.
A three-stop 'sprint' strategy to limit tyre degradation and gain track position is theoretically possible, but, as ever, drivers attempting it will be at the mercy of traffic.
Verstappen poised to provide fireworks at 'home' race
In his fledgling Grand Prix career, Verstappen has started from outside the top 10 on five different occasions. On all but one, he has failed to finish - and when he did (in Canada), he came home 15th. With a grid penalty consigning him to 18th at his ‘home' race, the Belgian-born teenager certainly has his work cut out.
That's the bad news. The good is that Verstappen has previous at Spa - fairly sensational previous. Rewind one year to his time in F3, and the Dutchman swept to a hat-trick of victories at the Belgian circuit, one of just two clean sweeps he managed all year. What's more, he didn't achieve any of those wins from pole; instead some sensational race craft - including a double-pass on the Kemmel straight - paved the way for his triumphs in all three events.
Can he repeat those feats on Sunday, and charge up from 18th on the grid? Don't bet against it - especially given the swashbuckling bravado and skill he has displayed on numerous occasions already this season. As the man himself says, "Good that I love overtaking"...
Very little to separate Williams, Force India, Lotus and Red Bull
For the first time this season, Williams, Lotus, Force India and Red Bull respectively locked out third through to sixth respectively - and just 0.102s split the quartet. Battle, therefore, looms large.
What makes the potential fight so fascinating is the dynamics of each team's relative strengths. Red Bull, for example, weren't necessarily expecting to run well at Spa given it is a power-dependent track. The RB11 has therefore made its time in the middle sector, where Ricciardo and Kvyat have looked particularly mighty. In a straight line, however, both men could be sitting ducks - Ricciardo was 16th fastest in the S1 speed trap in qualifying, better only than the two McLarens and Marussias.
Force India, in contrast, struggled in the middle sector, but were rapid in the first, with Perez and Hulkenberg the fastest two men in the speed trap. Lotus likewise are quick on the straights, while Williams are somewhere in between - all of which suggests we could be in for an enthralling multi-car scrap on Sunday.
McLaren searching for signs of progress
Heading into Spa, Honda had talked of their ambition of matching Ferrari with the upgraded power unit they would be introducing. Its debut fell very short of the hype.
Rather than thrust McLaren up the grid, Honda's power unit left Jenson Button and Fernando Alonso languishing in 17th and 18th respectively in qualifying - even before being sent to the back thanks to a combined 105-place grid penalty. What's worse, Button was around a second adrift of Felipe Nasr's Sauber ahead despite one of his "best laps in a long time".
So where next? Button and Alonso have already resigned themselves to a lonely race, with their most likely competition each other rather than any rival teams. But both McLaren and Honda are also scrabbling to understand why their hoped-for improvements failed to materialise. As Button himself said, a lot of work is still needed to get back to a level both drivers can be happy with. In the hills of the Ardennes, McLaren are still searching vainly for any kind of breakthrough.
Could the fickle Ardennes weather spring a surprise once more?
Rain and Spa-Francorchamps: to many the two are inextricably linked, such has been the frequency with which the wet stuff has fallen on a Grand Prix weekend in Belgium over the years.
But to the amazement of many, not a single drop of rain has filled the air this weekend, nor has the temperature dipped as unseasonably low as it has in the past. Instead we've had beautiful blue skies and surprisingly warm temperatures - much to the delight of the legions of fans packing out Spa's legendary campsites.
However, it wouldn't be Belgium unless there was at least the threat of dramatic weather on the horizon, and rather tantalizingly many forecasts point to the slim possibility of rain arriving at the very end of Sunday's race. If it does then you need only look back to the 2008 race to see what kind of drama could be in store. Back then heavy rain arrived three laps from home as Kimi Raikkonen and Lewis Hamilton fought tooth and nail over the lead. In the end Hamilton took the flag (only to be subsequently demoted) and Raikkonen ended up in the barriers.