Am I choosing the right coilovers, and what supporting mods do I need?

echoshotz

I run the XR1s with the true-style rear setup, found it was much easier to setup preload/ride height and everything. That being said it's still very doable with the oem style. You'll probably need camber arms (spl being the most sturdy and no bs option, not to mention easiest to adjust for the alignment tech. spc usually being the cheap alternative) and you can go with toe bolts to help get rear toe in check. Some people get toe arms instead of the dumb bolts (my opinion) as its less likely to slip. You can get a toe link with a spring bucket for OEM style rears or a simple (cheaper) toe link if you go with true style rear, as the toe arm wont need to have a bucket for the spring anymore as you've relocated the spring. I run the simple toe arm from SPL. Front camber/caster is not adjustable from factory so to get front camber in check, which a lot of folks dont, you'll need a front camber arm (A-shaped thing). Again SPL vs SPC vs Z1. Your pick. Most guys run SPL.

To answer your question, or TL;DR
The most necessary mods you'd need are rear toe bolts and rear camber arms no matter what coils you get. My recommendation? Get aftermarket toe and camber arms and skip the toe/eccentric bolts.

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2014 Solid Red Nismo 370z
Motordyne|Synergy Composites|Stance Suspension|Recaro|RJM|EVOR