Here is an article that explains their chassis advantage
http://en.f1-live.com/f1/en/headline...29102102.shtml
"After the car won three-quarters of every race so far under the 2009 regulations, Alex Wurz has revealed the secret of the Brawn BGP 001.
At times last year, the team's predecessor Honda had five wind tunnels at its disposal, according to Germany's Auto Motor und Sport, as well as a half-billion euro budget.
"The car was taken in three different directions in the wind tunnel," test driver Wurz told News. "Two directions were found to be wrong, so the team could just switch."
Amid the shock of the global economic situation, Honda then pulled out and the Brackley team was rescued by a management buyout headed by Ross Brawn.
"The Brawn is probably the most expensive car with the lowest operating budget ever," the Austrian admitted.
Wurz meanwhile gives Sebastian Vettel ‘ten out of ten’ for dominating last time out at Silverstone, but doubts Red Bull will have it so easily for the remainder of the season.
"I would say that Brawn and Red Bull are at eye-level, and success from now on will depend on the circuits."