THE STi's suspension has also been strengthened to cope with the improved engine performance. The suspension - front and rear - is a lightweight inverted MacPherson strut setup with offset coil springs that has filtered down from Subaru's WRC cars. The inverted struts provide for higher bending rigidity - compared to the conventional strut arrangement in the standard Imprezas - courtesy of a larger damping tube, which in turn produces less damping fade as a result of the increased piston size. The STi retains the WRX sedan's cast aluminium lower front suspension arms, which help reduce unsprung weight.