The ride-height approach behind Hulkenberg's excellent US GP sprint qualifying

Nico Hulkenberg's journey to a surprise fourth place in qualifying for the United States Grand Prix sprint hinted that Sauber had been aggressive with its ride heights for the 19-lap race on Saturday, as the German felt he'd hit "the sweet spot" with his set-up.

Having been concerned that his route to second in FP1 was "too good to be true", Hulkenberg looked at ease with his Sauber machinery throughout sprint qualifying and was ultimately half a second off Max Verstappen's pole lap - which was still good enough for a second-row start.

In fact, Hulkenberg had not been outside of the top five in any of the three sprint qualifying sessions - and will start tomorrow's shorter race alongside Oscar Piastri on the grid.

While Hulkenberg theorised that he might struggle to duel with the historically quicker cars around him, he nonetheless felt he could battle to stay within the top eight to secure his first F1 points since his Silverstone podium.

"I'm satisfied, happy as you might imagine," Hulkenberg said. "Obviously, in FP1 things were looking good already, but it kind of looked too good to be true. 

"We weren't sure if that's the real deal or what other people were up to with their programme. But we were able to continue that trend.

"The car felt quite all right; your own feeling and perception maybe doesn't always match what the lap times say, but the stopwatch doesn't lie, and that looked pretty good all day.

Nico Hulkenberg, Sauber

Photo by: Simon Galloway / LAT Images via Getty Images

"The pace was just there. The car seemed to be fast here and in a good window, it hit the sweet spot and I think that's all. Plus, I like it a lot here. It's a fun track to drive.

"I think it's going to be difficult [on Saturday], even though it's not a full race, but even in the sprints there's a bunch of really quick cars, with usually also a little bit better tyre deg numbers. But we'll fight, see what we can hang on to - hopefully something rewarding."

Hulkenberg's performance rather correlates with sporting director Inaki Rueda's comments earlier in the day, which addressed Sauber's strengths and weaknesses over the year.

Rueda explained that the car was more sensitive than most to being run "on the deck", an area where it can find larger aerodynamic benefits from the underbody. At higher ride heights, the C45 is a little more affected versus the cars close to it in the championship.

Although the Circuit of the Americas is known for its bumpiness, which changes slightly every year (the circuit was built on clay soil, which is prone to shifting due to its malleability), recent resurfacing has quelled some of the more extreme bumps.

Furthermore, teams can take a more enterprising approach with their ride heights in a sprint race, knowing that they can raise the cars when parc ferme reopens after the race. Rueda alluded to that idea, knowing that it would be unlikely that a car would wear out its skid blocks beyond the permissible limit in a 19-lap race.

"I think the high downforce circuits [suit us more], but the high downforce is not the only component of it. I think the other part is smoothness," Rueda explained before practice on Friday.

Nico Hulkenberg, Sauber

Photo by: Sam Bagnall / Sutton Images via Getty Images

"There's no secret that a lot of the performance of our car is to run it as low as possible on the ground. It's not only us, but our car suffers a lot from not being able to do so.

"Having a smooth circuit allows us to bring the car on the deck. Budapest was a combination of low speed, so high downforce, with a very smooth tarmac. So it was quite nice. Coming here, the question we have right now is how smooth is the circuit, and how low can we run it?

"The ground recedes or settles every year. So these big bumps develop at a very high speed. If you have a car on the ground and you go over a bump, it just unsettles the whole car. We need to lift it. But then we lose performance everywhere else.

"It is quite helpful [that parc ferme reopens] because you can take a more aggressive approach. Another point on the equation of how low you can run the car; one is the unsettling, the other one is wearing down the skid.

"The sprint allows you to be a bit more aggressive because it's much shorter than the race. And then you actually measure the skid after the sprint. And you say, 'OK, how would we have fared with this ride height for the race?' And you either stay as aggressive or play more conservative for the race."

Additional reporting by Ronald Vording