well i would say the AGXs. Many of my friends have used them on the Z as well as other platforms and have had great results and on the softest setting good ride quality. BUUUT unfortunatly if the ground control coilovers you have are the same spring aggressive spring rate i remember from my set i had for another car, it wont improve your ride quality very much at all, all this also is according to your ride hight, if you dropped it alot that would probably be why your squeaking

but i dont know
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Many thanks to amys300zx for the sig and thanks to nate for the pics

