AST BMW M135i/M140i Lowering Springs (F20/F21)Give your BMW M135i or M140i the extra stance it needs with AST lowering springs. From the factory, BMW did nothing to enhance the suspension of the M135i or M140i compared to the regular 1 Series. Unfortunately, the car's handling doesn't quite match up to its power. AST lowering springs reduce body roll when cornering, squat during acceleration and nose dive under braking. They also give the F20 and F21 M135i and M140i more direct steering with