I recently replaced the clutch and flywheel on my 2008 350Z with a JWT aftermarket combo. The dealership also replaced the slave cylinder. Now, from time to time it is very hard to shift into first or reverse, and I have to depress the clutch almost all the way to shift to any gear. In addition, 1st-3rd gear grind loudly after shifting. The service center claims all of this is normal with an aftermarket clutch, but I'm concerned that they are only trying to justify a half-@$$ job. I wanted to get some more opinions on the matter.
To test the throw on your clutch: Press the clutch pedal down to the floor, slowly, and take a careful note of the resistance you feel on the pedal. At about 7/8 of the way down you should feel the pedal go slightly less resistive. This is the 'throw over' of the diaphragm spring of the clutch pressure plate. If you can not feel this lessening of the pedal resistance you can adjust the pushrod on the clutch master cylinder. The push rod comes out of the master cylinder and has a locknut and thread on it, it is attached to the clutch pedal. Loosen the locknut and lengthen the pushrod by turning it to the right as you look at it. Give it a couple of turns and try the clutch for throw-over again. Adjust as necessary. You might know someone with a manual clutch car to get a comparison feel for a good throw-over. You dont need to have the engine running when doing the adjustment.