Any 24-hour race has plenty to contend with, not just against the clock. it’s an extreme test of machinery, team operations and driver skill but Spa has plenty of other factors to throw into the mix.

From treacherous weather to a shaken-up grid, here’s the unexpected you can expect for this year’s 24 Hours of Spa.

Weather

Race start and end will see the highest temperatures, although still quite cold.

A cloudy and very possibly wet 17C is set for the 16:30 start and Sunday is predicted to be a little warmer, with the race finish due 19C.

Overnight, temperatures will fall sharply, at their lowest around 06:00 at about 11C. That’s less of a concern, however, than the continuous, 80 percent chance of rain.

Although mixed conditions can produce exciting, competitive racing the risk of extremely heavy rain is a situation like 2019’s, where racing was neutralised with a safety car at 04:00 and then stopped altogether at 05:43 through to 11:30.

Spa-Francorchamps has had significant upgrades since then, including hopefully better drainage and less risk to cars sliding through Raidillon and being sent back into the traffic behind them, causing lengthy clear-up operations and potential injuries to drivers.

If the race can avoid a red flag in wet conditions then that’s a ringing endorsement of the changes made to Spa and hopefully sets up a very closely-contested year without major interruptions.

At least there’s not likely to be snow, as there has been at the World Endurance Championship race in Spa.

A strange starting order

The weather has very much already played a role in this year’s proceedings, heavily affecting pre-qualifying and qualifying sessions and cancelling Thursday’s night practice altogether.

A particular quirk of the conditions is that Pro teams were heavily disadvantaged in qualifying.

Because the three-person teams did not run in Q1, the only session with dry running, their averages were slower than many Bronze teams and some found themselves right to the back of the grid.

A Bronze car is on pole, with another in third place.

Meanwhile, the Iron Lynx Pro car, the furthest back of any, will start from 62nd.

The models of cars are the same, regardless of class, so it’s possible for a Bronze squad to fight for an overall win against Gold, Silver , Pro-Am or Pro cars.

Every car is built to GT3 rules this year and a Mercedes-AMG GT3 or Lamborghini Huracan GT3 EVO II is delivered to the garage the same, whether they’re Iron Dames’ Bronze squad or GruppeM’s Pro team.

The difference in speed would be expected to come from the input of the drivers, with Pros rated more highly and much more experienced and within the teams, where Pro outfits might have more resources and operational capacity trackside.

Every driver and team has the chance to prove themselves, though.

The ratings are based on experience and previous results and definitely don’t dictate pace or put limitations on a team.

Iron Dames, in particular, who qualified 12th, have just come off the back of a near-podium at Le Mans and have to be considered a serious contender both in terms of a highly competitive driver lineup and a team operating really well in endurance racing currently.

The #23 Grove Porsche, which Earl Bamber took to 17th despite being disadvantaged by track conditions in Super Pole and the #79 Haupt Motorsport Mercedes in 18th that Jordan Love will be running stints in, have strong starting positions given the size of this year’s field.

Being in the top 20 puts more than 50 cars behind them, a sizeable advantage even in such a long race.

Hares and tortoises

Slow and steady are not words anyone would associate with the 24 hours of Spa.

There is clearly an advantage, over a few qualifying laps, to being in a Lamborghini or a Porsche, though and that could be overhauled in the race.

Any car make can suffer reliability issues during the race and any driver or team can make a major error, the shared risk of an early end spread fairly evenly over humans and machinery in a day-long competition.

In race trim so far this year, though, the Mercedes and BMW cars have seemed to have the edge over the Lamborghinis and Porsches.

The season so far has run to only a 3 hour and 6 hour race at Monza and Le Castellet, very different tracks to the brutal challenge of 24 hours at Spa but that might still be some encouragement for teams who suffered issues during qualifying.

The #3 GetSpeed Mercedes qualified 63rd, after a frustrating session for Alex Peroni and his teammates.

Certainly not where they would have wanted to be but a better position than the #75 Sun Energy 1 Mercedes, which will start from the pit lane and as a completely new car.

The original was wrecked during Kenny Habul’s heavy crash at the end of pre-qualifying, which left him with injuries too severe to continue the race weekend.

His replacement, Liam Talbot, will drive alongside fellow Australian Chaz Mostert and teammates Nicky Catsburg and Martin Konrad.

Without having participated in qualifying, the new car has seen its first running during the short warm-up session after a scrambled preparation at HRT’s factory across the German border.

Being on-track at all is a good result for the team, who are no doubt keen to fight up the order for Habul.

The race will start at 16:30 local time (00:30 AEST) with 70 cars contending. That’s about as much as we can be certain of, until it all plays out in the chaos, courage and brilliance of pushing cars to the limit around Spa.