FINALLY, someone addresses the "clutch orifice". We had problems with our clutch on our G35 from the day we brought it home. I NEVER KNEW what this clutch orifice was or even excsited. Thanks for addressing this issue that nobody else knows about. We thught our new Master and Slave were falty, nope. It was the "clutch orifice", which cost $180.00. We bought it from a Houston dealership. ...I hope it is not counterfit... Have a good Holiday Season.
What I found out, was that this "orifice" restricts the fluid on the return, when you let the clutch out. As your clutch pedal returns up, the orifice reduces the fluid flow, slowing it down. This keeps your gear from disengaging too rapidly. I do not know the science behind this, but I have to assume that if the gears disengage too fast, there may be a grind out effect, but again I am not sure, But, what I am sure of, is that this little SOB causes a lot of grinding in or out anyway. Again, many thanks!
Thanks a lot for this information. I agree with you that the orifice would cause the clutch to disengage more slowly but I do not think that would cause any grinding of gears. Once you engage the gear you're going into with the shift lever as long as the shift lever is fully seated in position you should not grind gears no matter how fast you release the clutch. What this would do however is cause the engine power to be delayed and getting to the transmission when you release the clutch. In effect it would actually prevent you from dumping the clutch and I guess thereby helping to save friction material of the clutch and reduce the possibility of damaging driveline components. That's the only benefit I can see. But if you know how to drive a stick properly, then you know how to drive a stick properly, and this is not needed.