JMortensen

This will show you how to disassemble the inners: http://forums.hybridz.org/index.php/topic/105657-300-zx-turbo-cv-shaft-disassembly-and-reassembly/page__p__988589__hl__%2Bcv+%2Bdisassembly__fromsearch__1?do=findComment&comment=988589

Aha! The light goes on! Thank you. Yeah, NewZed is right, it's a function of the clearances between the ball bearings and the races, the friction of the balls against the cage, the grease, etc. When you have the joint apart, that's the time to look for problems. The most common problem is pitting of the balls or of the races. There isn't a hard fast rule about when is too much,but that's generally what you're looking for. I have some Porsche 930 chromoly race CVs that are LOOSE, and most of the factory ones are TIGHT, but I don't think there is any particular harm in running a loose joint or a tight one, so long as the ball bearings and races are in good shape. The inner and outer CVs have different size ball bearings in them. I don't think that it is possible to assemble them wrong, but that's about all I can come up with as far as things that could have been done wrong.

Sorry, but I have no idea what that means. Maybe a picture would help?

Is it safe to assume you have the CV plugged all the way in until it clipped into the diff, and that you have the inner CV's on the correct sides? There needs to be slack in the side gears and this translates to some vertical motion in the inner CV shaft. I don't have a spec on it, but I just went and checked and my LSD has probably 1/16" on both sides, and they feel pretty equal.

I've seen pics of cars (I think Ron Tyler and Paul Ruschman either built the cars or had something to do with them) where the front inner fender was cut out under the battery tray and a new battery mount location was built off of the frame rail. Same position basically, but down a foot.

Funny, I don't think I told the machinist which side was inner and which side was outer. The CV inner races are different thicknesses. I don't think you can screw it up, because you won't be able to get the snap ring or circlip in the thicker side. There isn't a huge difference and I didn't actually try to put the wrong side on and see if it worked, but I'm pretty sure that's right... EDIT--Also the groove for the inner circlip is deeper and wider than the groove for the outer snapring.

The age old mod is the JTR up 3/4" out 1/4" relocation. IME though, it only took ~7/16" up to get as close as possible to correct. So are they right, or am I or is it somewhere in between? Slotting allows you to move it while measuring bumpsteer. I had never heard of JTR when I did mine, I just figured I could move it and measure and get it right. Redrilling means that you're relying on my measurements or JTR's or somebody else's.

There would be a little bit, if you have the driveshaft and halfshafts disconnected, might be 1/8" or something like that. If you still have all the rest of that connected, then it's very very difficult to feel anything accurately as described here: http://forums.hybridz.org/index.php/topic/105207-the-dreaded-diff-clunk/ If you really wanted to see what the backlash is, the correct way to do it is remove the diff, pull the cover, and measure with a dial indicator.

The bind that I'm trying to fix is a bind in the length of the CV axle. The CV axle is just too long to fit without some load on the diff when you use stock control arms and stock Z31T CV axles. Having figured out the bind and fixed it before actually assembling my own car I've never actually tried turning the wheel and feeling for resistance with the bind in place, but honestly I don't think you're all that likely to feel resistance from the bind by turning the wheel. I would guess, and it is just a guess, that you have a rotor that is moving on the studs as you turn the axle. You could fix this by putting a couple lug nuts on to hold the rotors in place on the stub axle while you are turning them. This would explain both the clunk (rotor shifting) and the tough spot (pads dragging on the rotors). If you have MM's Extreme kit you might also look at using a dial indicator to true the rotors before you run them. This has been discussed previously, but basically it involves using stainless shims between the rotor and hat to get it trued to less than .002" runout. This will ensure no brake shimmy, and it's not that hard to do. I do think you would be well advised to buy my short shafts regardless of whether an out of true or loose rotor ends up being the cause of your issues. Based on my calculations there should be no way that you can run the welded adapters and the stock shafts without significant bind unless you have a control arm that is something like 3/4" longer than stock, and at that point it would JUST BARELY clear. I've got some shafts on order right now and they should be here in a few weeks. You can get the group buy price if you sign up before they arrive.

I don't know of any reason why the two joints would need different lubricating capabilities, they're both the same kind of birfield joint. I would suggest you use an extreme pressure moly grease. I honestly don't think it makes that big a difference which moly grease you use, but Coffey has made a grease recommendation of Wurth SIG 3000, and I'm a fan of Wurth lubricants, so if you are looking for a brand name, I would try his suggestion.

Or an adjustable rear on a soft setting might be worth a shot.

My control arms have rod ends so I had to make spacers, and they're thicker than what you would have if you were using stock or poly bushings. There is no washer on the inside of the crossmember on my car. If you wanted to keep poly bushings or not have to mess with spacers, then I would suggest that you drill out the old washers, drill the hole up 1/2", and then weld the washers back in the new spot. That should be pretty close to correcting the bumpsteer. If you want it exact and you have to make spacers anyway, then I like my slotting method. Mine is a dedicated racecar. You'll have to weigh the modifications for yourself and see what you think is best or safest.

blueovalz made some steering stops when he installed a Ford PS rack. Here is one pic but the rest of them are worth a look too. The guy is quite the fabricator and extremely willing to help, but he sold his Z and is now onto a crazy Manta: http://www.fototime....reenheight=1080 FWIW I had some rubbing but never had the TC rod self-adjust. That's pretty scary.

Not sure about the heat issues. My point was that you can weld stainless with regular wire. I was totally unaware that you could do that until my bro-in-law bought what amounts to a Z junkyard about 5 or 6 years ago. I went down to help him move all the stuff, and part of the deal was that he got these huge steel racks that the doors were stored on (pretty sure they were Home Depot racks). We loaded them into the truck and one of them started to fold. The guy who sold us all the stuff had a big 220V miller and a nice welding table with a bunch of scrap under it. I grabbed a piece of scrap and welded a brace on to hold the thing together, and he came back a while later and said "Why did you brace it with stainless?" I said I had no idea it was stainless and that I didn't even know you could weld stainless with regular wire. He said he didn't know that either, but there it was, and it held up just fine.

There is no piece of metal on a Z that is thicker than about .100, MM140 will do fine. You can weld non stainless wire to your stainless exhaust, so if you had a muffler you wanted to use but you didn't want to buy a tig you could just weld it up with the regular wire. Won't resist rust like stainless, but you can attach it just fine.

Me too. Ran my L28 on DELO for years after it was recommended by a race shop.

You might want to factor in some room for a hardened washer on each end of the spring.

The modern Subaru R180 bolts in. Unless they made a different short nose R180, I'd say it's probably going to fit. The real issue might be the output shaft splines and retention mechanism on the Xterra. Bjhines was nice enough to give pictures on how to convert a 240SX with circlips to bolt in and I put that info in my big diff thread. You might need to do something like that. It might also be possible that it uses the same splines as the Subaru, in which case you need Coffey's adapter diff output stubs. I think you'll have to check it out to know what you're up against.

Clunk clunk clunk doesn't sound like LSD to me. Chatter is more of a bang bang bang. Wheel bearings are usually load sensitive, so the test is to swerve back and forth hard and listen for a groan. I don't think you'd hear a wheel bearing turning around in a parking lot, for example. If you want to check the CV length the thing to do is remove the springs and then push the suspension through its range of motion by hand. I'd check the stub axle, seems like some people get a clunk before it lets go all the way. It's kind of tough to identify noises on the internet though. Good luck with it.

Drag racing starts/dropping the clutch puts a huge load on the axles.

That original statement that the Z31 shafts are the right length is a mistake. They do bind. I covered why you can't just cut the splines further down the shaft in the other thread, but I'll post that picture here again too. The problem is that the CV shaft tapers down from the splined area, so there is no metal there to cut. Yes, the Z31T shafts plug right into a standard 29 spline open R200 out of a 280Z. The only exception is the 88 SS version which came with a VLSD that had 30 splines. The companion flange is not the part that normally breaks. It's usually the stub axle flange where the wheel studs are, or the end of the stub axle shears off where the splines are. You might very well be fine with stock 280Z stub axles and the CV conversion. If you're drag racing part of the game is shock loading the axles. Obviously that's worse if you're on slicks, but somebody who drag races could give you a better idea of when you might expect to have a problem. Best wishes for your woman. I've had mono, it's not fun.

I don't have a torque number for failures on these things. I can say that it seems that the flange failures are more common than twisting the shaft off. Maybe some of the drag racers could answer that question better than I can. The splined shaft part of the CV that you linked to fits into the diff. The 4 bolt part bolts to the CV adapter, which is the companion flange to the stub axle. So you still need stub axles, and you still need the companion flange. Stock Z31T axles are too long and the bind can cause diff failures. Here's the M2 group buy for the CV adapter (I have these in stock right now): http://forums.hybridz.org/index.php/topic/105514-m2-cv-adapter-for-z31t-cv-280z-stub-axle/ Here's the M2 group buy for the short axles (on order, should be available in 3-4 weeks): http://forums.hybridz.org/index.php/topic/105510-m2-z31t-short-shafts-group-buy-2/ This is an install thread of the short shafts: http://forums.hybridz.org/index.php/topic/103391-z31-axle-swap-r200-clsd-m2-differentials/ And here is the discussion that led to M2 making these parts: http://forums.hybridz.org/index.php/topic/103391-z31-axle-swap-r200-clsd-m2-differentials/

Just out of curiosity, what does it take to be a good design? If a GT3 cup car is 20 seconds faster around a road course than your Z when its all done, is the GT3 still a bad design? I used to work at a Porsche shop and poke fun at the customers who poked fun at my Datsun. I'd tell them that driving a Porsche is like throwing a dart backwards, or that I'd rather have 6 in the front than 6 in the rear, but realistically, there are a hell of a lot of Porsches that are faster than my Z will likely ever be. For axles, I don't think you're going to do better than Chequered Flag and that's about $700 if I recall. Then you can buy adapters for CVs from me or Joe [me] and if you get my short shafts you'll be into it $1500. That should be enough to move the weak link in the chain elsewhere.

You mention getting sideways. Are you going to install a hydraulic ebrake? That might work, I haven't used one on this system, but the regular ebrake is good for parking and not so good as an emergency brake.

The early version has a deeper hat on the rotor and has a huge, heavy caliper with smaller pads. If my choices were limited to the two, I'd go with the later version, but really both of them are too small for most of the common front brake upgrades. I actually had the ZQuip brackets and the early setup just like was in the first edition of Z Car Magazine way back when. It worked really well with stock front calipers, but when I went to Toyota calipers I could never get enough rear braking.