The front splitter, the rear apron, sill panels, as well as changes to the body in the area of the rear window (C-pillar) and the bootlid improved the aerodynamics. For aerodynamic reasons, the rear window was flattened and the tailgate was made of light, glass-reinforced plastic raised by approximately 40 mm for better air flow. The changes over the rear of the car resulted in lower lift forces and better straight-line stability. In addition, the windscreen was glued in – not, as with the other E30 models, framed with a window rubber and piping. As a result, the M3 achieved a relatively low instead of as in the standard 3 Series. The only exterior body panels the regular 3 Series and the M3 shared were the bonnet, roof panel, sunroof and inner door panels.