All you need to know with the springs is this. If you want to go the lowest possible with springs then get H&R. Swift is highly recommended as the best for the Z but if you want no gap you will not get there with them. I can still get about 2 fingers between my tires and fender. Swifts are 1.25" FR and 1" RR if I recall correctly. The H&R's are 1.3" FR and 1" RR but other members have shown that these settle alot more and the drop is more significant. Check with our vendors to get the best pricing. Lots of threads on this to see pics to help you decide.
Swift springs review!!!!!
Eibach Vs. H&R springs..