Sauber will go into this morning's postponed qualifying session for the Japanese Grand Prix blind having been unable to try out significant setup changes made after Friday practice.
Nick Heidfeld and Kamui Kobayashi completed just one lap apiece in Saturday morning's rain-hit free practice session. The team introduced its last major upgrade package of the season on Friday, but will not know whether the changes made in the hope of getting the best out of the development parts have worked until the C29 runs in the dry.
Technical director James Key agreed that the decision not to hold qualifying on the waterlogged track was the right one, but admitted that the team was in need of dry mileage.
"We really could have done with a run on Saturday because we made a lot of set-up changes overnight," Key told AUTOSPORT. "There were weaknesses in the second sector during Friday practice, and we won't know until we hit the track in qualifying whether [the changes to correct that] worked. But it was a wise approach by the FIA as it was clear that the conditions were getting worse rather than better."
The package includes a new front wing, a turning vane and other bodywork tweaks as well as modified brake ducts and a new diffuser.
Key was happy that some parts of the package had performed as anticipated, but admitted that there are still some question marks over some of the changes at the front of the car. It is hoped that the setup changes that have yet to be tried in anger will resolve any problems.
"It's a mixed bag at the moment," he said. "The downforce is there, which is good, so the numbers that were were expecting to get are on the car. We've got a few questions over a couple of areas around the front of the car that we need to confirm further at the moment. We're looking to see if the effect that we are getting from those parts is what is expected. So there is an element of investigation on the front, but certainly the diffuser and rear brake ducts are doing as we expected."