Sauber are working on a new lightweight chassis which they hope to debut at the Spanish Grand Prix, in the hope of meeting the minimum weight allowance.
The team have been struggling to meet F1’s new 692kg weight limit this year due to a new heavier power unit, heavier tyres and a heavier safety structure.
The C33 is believed to be about 20kg overweight and the team are hopeful of losing that amount, which it estimates is costing them about six tenths a lap.
The revised chassis should be ready in time for the first European race in May, according to team principal Monisha Kaltenborn.
“We are planning a big upgrade for Barcelona introducing measures on the weight side,” she told Autosport.
