stupid question

why dose it say that its not for the street and how would they react on the street



http://store.summitracing.com/partdetail.asp?autofilter=1&part=EIB%2D9307%2D140&N=700+4294925130+4294908216+4294908198+4294924760+ 115&autoview=sku

Street handling would be sloppier than normal, since the springs are designed for weight transfer during straight line operation.