The clutch hydraulic system in the Z just plain sucks. I've had Z1's kit for 2 years now. And still having master problems. I'm in the process of installing the new RJM HD master. I am fully expecting that to solve my problems once and for all.
If you like tinkering with your car and don't mind a little adjusting or part replacing if tracking hard, the Z1 kit is great because you can essentially replace anything in the clutch system without ever having to drop the transmission again (once installed). But if you want maintenance free, 'I don't want to mess with the slave at all', then the ZSpeed HD slave is probably your best option.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |