Sauber C23 - new engine cover 11 July 2004
1) Hot air vents on the top of the sidepod rather than the outer edge. 2) Lower, more sculpted rear bodywork, with taller chimneys. 3) Horizontal element in front of the rear wheels, connected to the engine cover by two curved fences. 4) An additional mid wing just behind the onboard camera support, giving the car better balance.