Mercedes will switch Michael Schumacher's car for next week's Spanish Grand Prix to try and get the seven-time Formula One champion back up to speed, team principal Ross Brawn said Monday. “It's not a new chassis per se, it's a chassis we used in testing,” Brawn told Reuters at a fund-raising event for the Royal National Lifeboat Institution on the banks of the River Thames. “The one he had got damaged during the first few races and we repaired it as best we could at the races. But now we are back at base we are going to re-introduce the test chassis and he will be using that in Barcelona.” Brawn said the wheelbase would also be changed to improve weight distribution, and Mercedes are also planning a major aerodynamic revamp for the first race of the European season after four in the Middle and Far East. Schumacher, a winner at Benetton and Ferrari with Brawn as technical director, is making his Formula One comeback at the age of 41 and after retiring at the end of 2006 with a record 91 race wins.