Mercedes expects that the new floor that was abandoned after Friday running at the Belgian GP will be back on the W15 at the next race at Zandvoort.
In initial running at Spa with the full update package the drivers experienced bouncing, with the team believing that mechanical set-up issues were the problem.
After overnight work both in Brackley and at the track it was decided to go back to the previous floor for Saturday.
The car was much better in the wet qualifying session, in which Lewis Hamilton qualified fourth.
However even Mercedes was surprised by the car’s pace on Sunday, with George Russell winning on the road and initial runner-up Hamilton inheriting the win after his team mate was disqualified.
“On Friday we were not competitive, but there wasn’t a clear direction,” said team boss Toto Wolff. “And honestly, I must admit that the overnight work that was done from Friday to Saturday in Brackley in the sim and also here on the track side, engineering side, was the key.
“So we remedied that, but we didn’t see the pace [in the race] as it actually came in. The car was quicker. And we had control of the race either with the one-stop or with the two-stop. So that’s the positive to take from the weekend.”
Wolff expects the new Mercedes floor to be reintroduced at Zandvoort and potentially compared with the older version in a back-to-back.
“We made a drastic change in order to recover some of the performance, and we believe it was in the floor,” he said.
“So it will be quite interesting when we put everything on the car at Zandvoort and correlate, and see what one does, and the other.
“Then we can be sure whether it’s the mechanical bit that we thought we got wrong, or whether there’s a few directions, aerodynamically and mechanical, that didn’t work.”
Mercedes trackside engineering director Andrew Shovlin confirmed that it was the set-up, rather than the floor itself, that caused issues on Friday in Belgium.
“The reason we reverted the car to the Silverstone spec on Friday night was because we had a good race in Silverstone,” he said. “Spa and Silverstone are not dramatically different circuits in terms of the corner speed range that you are dealing with.
“We had clearly introduced some problems somewhere. We think that was largely due to how we were running the car in Spa, not induced by the updates themselves. That was giving us a bit of bouncing in the high-speed corners, as well as a few issues with the balance.
“Going to that Silverstone car got it all back to normal. We have since had time to look at the data to understand what it was that we did, and we are pretty confident that we will be going for a reintroduction in Zandvoort.”
Shovlin suggested that in Belgium excessive bouncing with the new floor was hurting the confidence of the drivers.
“One of the issues with Spa is it is a fast circuit, and it needs a lot of commitment from the driver,” he said. “We managed to introduce a bit of bouncing to the car, so in the high-speed corners that is not great for their confidence. There were a couple of other balance issues where they had a lack of entry stability.
“When you are wanting to brake late and carry speed into a corner, that does not help. At a normal track, that might have cost us a little bit of time. On a big circuit like Spa with some pretty big corners, that was becoming a large number.
“The car was not in the right place, but it is one of those very specific things about Spa where if the drivers have not got the car doing what they want, it can cost them a lot of performance. It was exactly the right thing for us to just revert to that known specification.”
