the riser bush see pic 1 bellow. replaces the factory subframe bush see pic 2 bellow. in doing this you raise the entire subframe approx 0.5-1" higher. how this works is the shape of the riser bush, one end has a shafered edge where the standard washer and bolt go see pic 3 and the other is dead flat making the top lip of the subframe sit flush on the cars rails, see pic 4. Having the subframe sitting higher will correct all the suspension geomatry from being like this \ / on a low car to this _ _ see pic 5 making the suspension work properly how it was designed. Replacing all the factory bushes in the rear end to urethane or even sepherical bearings. (most people just use urethane) Onto foam filling the subframe, you use a marine grade which sets extremely hard, this makes the subframe basically 1 sold piece reducing and movment within the frame itself. It is a 2 part foam that you inject into all the hollow sections of the frame.
Next is correcting the same thing for the front end. You drill your front Lower Control arm (LCA) upwards. See pic 6 Then the only thing left to correct is your tie rods, simply buying new tierod ends can fix this. See pic 7
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