i give the stock strut a little extra room to move. see, in order to lift the front 4" the coils only need to be roughly 2-2.5" taller. the front strut already has about 4.75" of stroke, more extension than compression at stock ride height, so, by building the upper strut mount with a flat top, minus the bell-shaped area, and trimming the bumpstop to about 1/2 or 1/3 it's stock length, one can keep most of their up travel and gain about 2" down travel. to be honest, the strut, at ride height, with my 4" kit, sits only about 3/4" further extended than it would from the factory. this leaves about 4-4.5" of extension and 4.5-5" of compression measured at the top of the tire. so, no, the strut will only top-out when getting REALLY flexed-up or taking a corner WAAAYYYY too fast.