Subject: Clutch / Trans R&R
From: "DOC'S" zdoc@yosemite.net
To: Bob <coolbreeze65s@thegrid.net>
Date: Mon, 8 Feb 1999Bob writes:
Hello Doc,
I will be replacing my clutch soon, and my 5 speed trans needs an overhaul. I would like to install a performance clutch set up. I've read that "center force" is a good set up? What would you recommend? The trans doesn't like to shift into 3rd, and when stopped, it's stubburn going into gear. How difficult is it to rebuild. What are the special tools? I have a spare, but I would like to rebuild the one coming out of the car. Should I replace the slave and clutch master cylinder at the same time? While I'm at it, what do you think about the quick or short shift set up?
Looking forward to hearing from you soon.
God bless,
Bob
Doc replies:
Hi Bob,
Doc here, what year is your Z? I suspect that it is a 280Z, & that would make it a 75-78 model.
First off, "Performance" clutches like the Centerforce work well, and the lockup physics are very good, but the question for you is do you really "need" this model? The factory style works very well without problems when installed properly, and will give you years of trouble free operation.
Secondly, if you are having a grinding problem going into a specific gear as you indicated shifting into 3rd gear if the synchro is going bad from wear it will be grinding upshifting and downshifting. The problem is not difficult to repair but it requires special tools and a surgery inside the
transmission. There should be an inspection of all the gears and bearings with seal replacement too. This is not your ordinary home job since it requires special tools for this operation.3rd, If you have another transmission then you can send that one to me for inspection, or put that one in the Z to drive it and sent the original one for inspection and repairs. Some models of the 5 speed transmission need a replacement mainshaft if it is the early one. The main purpose is to change the mainshaft locknut to the later style one that is a left-handed threaded one for longer lasting service. The earlier one can develop the stick jumping out of gear in 5th, or if the locknut backs off too much it will not go into 5th gear. I e-mailed a lady in Texas before Christmas about that situation and she then had the correct information to tell the service department what to look for and what to do, and she did not get the run around so that her transmission was repaired correctly, and at a lot less dollars spent on the old you need all new gears story.
4th, In the vintage of your Z I do not recommend the rebuilding of hydraulic parts. Replace the components, both the master cylinder and the slave and install new fluid when you bleed the system. This is the only safe way to not have to do the job again in the very near future. You remark that you had a hard time shifting into gear when you were stopped and that I believe is attributable to a hydraulic problem. For the rest of you out there I recommend the replacement of the brake fluid in both the clutch and brake hydraulic systems every year. Your components will last longer and you will not have the dreaded "sinking pedal" syndrome that comes from lack of this service procedure.
5th, For those of you out there who want the quick shift stick set-up and have the dollars and the time go for it! You will notice a shorter distance in the shifting from one gear to the next, and if you have a shoulder problem or that your arm is not long enough to shift comfortably it can help you. But if you think that you are going to cut your track times by any great measure you will find that you can only shift as fast as the transmission is capable of and no faster times that you will see. It is a matter of your reaction time. This is all to do with you, and not as much to do with the shifter. Yes the throw is shorter and in the one kit that I saw it comes with a weighted shift knob that you need to use, so your keeping that classic wooden shift knob will not help.
Well, Bob I hope that this gives you some food for thought, and some answers to your questions.......
If you need to call me at the shop:
Doc's Auto Clinic
209-742-6150 in the afternoons please til about 7:00PM PST
5104 Jessie St.POBox 1240
Mariposa,Ca. 95338
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