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seattlejester

Need some opinions on rear half shaft route with R200 VLSD

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Long and short of it. Need some ideas.

 

I have an R200 Long nose differential out of a Z31 300zx non turbo. I have swapped the ring gear onto a center section from an 1994 or 1995 infiniti J30, gaining myself an LSD. I am going to shim it slightly, clean it, and install the ring gear on and reinstall it into the housing finishing that part.

 

Now here is the problem, the input shaft while having the same spline count, have different lengths. The short side can be popped out and the R200 input shaft from a 280z can be used. The problem is the longer side is indeed just that, longer. Thus I need to use the input shaft that came with the infiniti. The connundrum is that it is a 6 bolt pattern 3x2 and fairly large about 2-3 inches longer as it is a cup rather then a flat flange.

 

Xenon31.com has quite a few methods, but rely on acquiring the highly lucrative 1988 Shiro VLSD axles for some of them. All the methods outlined is assuming a Z31 stub axle so would require converting the flange via whitehead performance or checkered flag racing conversion flanges for the stub axle.

 

I'm putting out about 300hp with 330ft/lb according to the internet. So it would have to handle that.

 

So my options I can see are as follows. 

 

1. Cut the infiniti input shaft and weld the flange on from a 280z input shaft and use rebuilt stock half shafts. 

 

2. Cut the infiniti input shaft and weld the flange on from a 280z input shaft and upgrade to wolf creek cv axles.

 

3. Retain the infiniti input shaft use infiniti cv axle (at least the differential side), shorten axle, and convert stub axle flange to match cv axle, will probably require 4 axles to use 4 differential sides.

 

Is there some other methods that are staring me in the face that I am missing? I know welding axles is a pretty big no-no, but is welding the shaft of the input shaft to a flange acceptable? 

 

 

 

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Hey,, I will message a friend a mine this morning and let you know what he says.. This may not be worth it to do...

 

I know he installed a J30 VLSD Diff in his 97 240sx but said it wore out in about 2 weeks.  His was a stock 240sx with stock Ka engine. So he put another one in and the same thing happened... Not sure if that VLSD is that strong. He would drift the car on the street, not at the track..

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Can't remember who it was but a Hybridz member extended the inner portion of the shaft that needed to be long by cutting and welding on another splined section.  It's all torsional inside the diff so the flexing and stress riser issues you'd see on the outside seem diminished.  He said it worked fine and hasn't been back to report a failure so who knows.

 

Welding the shafts affects the carbon content of the steel and the heat-treatment.  Most shops don't like to do it so you'd probably have to waive your right to complain if you had flanges welded on the outside.

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Thanks for that newzed. Hmm, I just figured it would hold up better to weld a flange onto the shaft then trying to cut a shaft shorter or to weld up a spline like that. I'll have to take a look when i get my input shaft to see what would be the most reasonable. And for sure I get that any shop doing such work would wave any responsibility. The part that appealed to me is that I think it was the input shaft that looks like it is welded. Kind of located with a hole that sits into it and then welded internally. I might be mistaken though.

 

Hmm well i don't plan on drifting with this diff so we will see, but I can't run a welded for daily Im just not as tolerable as I used to be, but please do ask curious I am

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Im trying to use a r200 from a NA Z32, and it has the same problem. It uses the 5 bolt flanges though.

 

I'm looking at using WD21 pathfinder v6 axle shafts to make hybrid axles. The center bars on the pathfinder axles have the same spline count and splined section profile as the z31 turbo axles.

 

This has been documented previously in order threads and forums, some modification is required to the axle shaft to get the inner race from the z31t outer CV joint to stay on the shaft.

 

Ideally, I'd like to see a companion flange get produced that uses the 5 bolt design at the wheel instead of the 4 and 3x2 (z31t, z31, and 280zxt styles) as the 5 bolt seems to be much more readily available than the other two which are becoming increasingly rare.

 

I'm checking to see if the inner races on the z31t, z32NA and z32tt are similar aside from the splines and could therefore be interchangeable.

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There's a nice picture on the internet. I completely forgot to grab the measurements. I'll grab them next time I'm playing with them.

 

So playing with this idea a bit, I'm coming down to two choices.

 

1. Cut the input shaft and weld the round portion to the round portion of the stub axle shaft. Then run wolf creek style porsche axle with adapters.

 

It might be my eyes playing tricks. And I need to find my calipers, but it almost seems like output shaft has a diameter that will slide over a stub axle flange. That would make it fairly centered.

 

2. Find the thicker axle between the porsche and the infiniti, have it turned and splined to fit the Nissan 6 bolt CV joint on one side and fit the porsche CV on the other side. Adapt, bolt in.

 

This seems like the more correct choice. The concern is that the joint for the nissan is quite long and that this will really really shrink down the axle length.

 

So some facts to consider at this point. 

 

Total axle length.

 

Given that a lot of baja/buggies like to adapt to porsche CV axles, it actually is possible to order a custom length axle off the bat or have a standard axle shortened and resplined. 

 

For the wolf creek style axle, the current measurement I am finding for axle length is 14.468 inches just for the axle. With the adapters this will bring the total length to _________.

 

This is for I assume an R160 in a datsun 510. Seeing as how Troy sells his axles without a separate option for both the 240z and the 510, it seems this size is adequate for the R180 in the Z chassis.

 

Listed on the wolf creek racing website, there was an option for R180 or R200 when purchasing the axle. According to past emails with Todd (RIP) he mentioned that the difference was the driver side axle is shorter for the R200 kit to allow for the larger differential size. Nominally people have said this value is approximately 1/2 an inch, that half an inch shorter on the driver side seems to make enough room to accommodate the R200 without starting to flex the suspension.

 

Of course this will all be verified once I get under my car for the actual lengths, but I think both are feasible.

 

The concern falls into one of two places.

 

If I go with option 1, I will be relying on a very special input shaft for the passenger side. The rest of it could in theory be ordered.

 

If I go with option 2, I will be using a very custom axle. The rest could be acquired at a parts store easily.

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None of my later options include using the Z31 parts, they seem to be difficult to find and when found seem to be quite expensive. 

 

I can stretch out my control arms a bit to compensate, but given some kind of custom axle will be on order, I will probably just get them a little smaller to compensate.

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So starting from scratch again, sort of.

 

XenonZ31.com has pictures again, I'm going to have to save those for later just in case.

 

Method one with pictures looks real promising for my case, it uses the tripod CV from the Infiniti J30 from 94-96 and puts it onto an NA Z31 tripod CV axle. The NA Z31 tripod CV flange has (if the internet is reporting correctly) the same pattern as a 280zx turbo tripod and so a companion flange adapter from Joe or Modern Motorsport should yield a straight bolt on setup. 

 

Problems that may occur are two fold.

 

1. Length. The method is for a seemingly bolt in setup for an NA Z31. That does not neccessarily mean it will transfer directly to the S30 chassis. In fact we know that the Z31T axles are already too long as it is, so this may end up being too long even though it is bolt in.

 

2. Parts. The 94-96 infiniti J30 axles can be acquired quite expensively through the parts store, the same can be done the NA Z31 axles. Right now, the only ones I have found easily want about 200$ for the NA Z31 axles and about 300$ for the infiniti axles. I'm hoping to go bother my local Napa to take some measurements, but if my eyes don't deceive me, it looks like Nissan used the same CV joint on quite a few vehicles. Pathfinders for example have axles that are quite short and also quite readily available and cheap running about 100$ for a pair. It also seems like these joints are available from sears at about 40$ a piece. Ideally I would have just taken the joints off at the junkyard, but as it sits now if the splines are correct, I may be able to get out of this with 300$ in parts or 500$ at most. The benefit also continues with the path finder axles as they are quite short. This would mean that I could make an axle and then space it out correctly with some simple aluminum spacers to take up any slack.

 

So it seems like this will be the route I follow for the moment.

 

The pieces of information I will need and will find out is...

 

Total length needed/used from differential to stub axle _______

 

Total length of 280zxt companion flange ________

 

Total length of infiniti differential input ________

 

Total length of CV joint _______

 

Taking the full length and subtracting all the above and accouting for how much axle sits in the CV joint itself should give me a small range for the actual axle shaft needed. 

 

This will of course be different for both sides. 

 

Part number for the axles used _________

 

ID of the axle used __________

 

CV joint spline count __________

 

Will go out and buy the CV joint from sears for testing and might pick up an axle or two once I get the bolt pattern down in detail.

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Will go out and buy the CV joint from sears for testing and might pick up an axle or two once I get the bolt pattern down in detail.

Some, maybe all, of the aftermarket new CV axles use standardized joints and center axles, with different ends to match the applications.  So they won't combine with a Nissan axle to make a hybrid axle.  Beware.

 

Remanufactured axles should work, but even those might be reman aftermarket.  Better examine closely before buying.  Check the axle manufacturer web sites and some will describe the details.

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Thanks for the warning, hadn't thought too much about the fact that could be done. The CV replacement part came up when searching for infiniti CV joints, so it came up with the one CV joint for a variety of Nissan Vehicles without any cross listing for domestics so I'm hopeful, but I'll be mindful. The spline count seems right so ever hopeful.

 

Thanks will do, some sights have been great about specs, others have been pretty lacking. I'm going to just try matching end to end, and see about ordering a couple to take apart. 

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Ordered an OEM replacement 27 spline CV joint for later nissans and a CV axle for a pathfinder. 

 

Seems like eBay has a couple turbo axles so I'm thinking of ordering one just to see if they fit and if not if they can be taken apart to use or if they use different CV's and just match of the flanges.

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So I looked up the part number that sears provides with the joint. It came up as the CV boot. After a bit of searching through Febest, I found that they only charge 15$ for the boot so paying the 50$ should indeed be a kit and that sears has the wrong reference number. Just received the joint yesterday, complete joint with boot, clamps, c-clip, joint, and housing. It is however missing the CV grease seal for the bottom kind of like a paint lid can. They probably expect you to take this off of the old joint since you will have to remove it to install the new one. 

 

50$ CV pathfinder axle came in, made in china, looks to be a genuine copy it has the same grooves and such. Planning on removing the hub shaft to get to the splines, waiting on my second 280zx turbo axle to come in. This is apparently used quite a bit by the 510 guys, it is shorter then a 300zx turbo axle so a better fit for them potentially. 

 

First 280zx turbo axle has come in, it looks a bit long, but the listing says it is for the 280zx turbo. The bolt pattern is smaller then the 3x2 pattern used on the later joints fits the turbo cv adapter perfectly, but will not fit the input flange.

 

Driver side is theoretically done. 27 spline 280z stub axle, to 280zx turbo cv adapter, to 280zx turbo cv axle. 

 

Passenger side may need a shorter axle just based off of eyeballing. It will be the 27 spline 280z stub axle, to 280zx turbo cv adapter, to 280zx turbo cv, to pathfinder axle, to path finder cv joint, to infiniti input shaft.

 

I am hoping that the path finder axle and the CV joints can compress enough to fit in without binding. If that is not the case, I hope the 280zx turbo axle is a full length axle and can be cut down and resplined to accommodate the pathfinder cv joint further down. If that doesn't work I will have to find an axle that is fairly large to be turned down and splined to fit both the cv joints. 

 

More information and specs once I pull apart the second turbo CV and find my micrometer.

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So some progress.

 

Haven't been able to find my second micrometer, so I think I'll be purchasing my third....

 

Disassembled the pathfinder joint, didn't have the correct punch for the cv joint so I smashed the cage until it released the CV and pressed the gear off. The compression ring broke a couple splines off so seems like 40$ for a complete axle was most likely a justified pipe dream. Regardless, even this axle is too long.

 

The 280zx turbo axle is sufficient length for the driver side with the adapter. The herri axle seems to indeed be made for the 280zx turbo.

 

After some searching and figuring, it seems like you can order just the joint from the 280zx as well for the thinner 3x2 bolt pattern.

 

If the illustrations are correct (still need to go measure), the 3x2 pattern used on the 280zx is 98mm (also used on g35), while the one used on the infiniti j30, pathfinder etc is 126mm.

 

I took the plunge tripod joint from the 280zx turbo axle, turns out it has a fairly large tripod bearing race. The one from the pathfinder axle has a smaller bearing shorter race, but it just barely fits into the 280zx housing. My spare joint I bought for the infiniti has a large joint with the same spline so I think that will work with the 280zx housing. If it does not I will source the g35 tripod as I believe that will still fit the WD21 axle.

 

So as of now I have both joints solved or can be solved, I just need to figure out the actual axle.

 

The pathfinder axle looks to be about an inch or so too long. One side has a hard stop and necks down right after so it excludes the possibility of machining. The other side however doesn't seem to neck down for 2-3 inches and has no visible hard stop, just the splines end. I am really hoping that the micrometer says that it can be machined as that would be a simple case of lopping off an inch or two of that end having the splines cut and having a couple groves cut to hold some C clips. If that works I should have a bolt in setup!

 

I do have all the stock pieces so once I acquire another micrometer I will take measurements from the differential input to the hub and the thickness of each piece which should help others cobbling together a similar setup.

 

The concern at the moment is that if the axle does neck down and cannot be splined, where would I go about acquiring a custom axle? As mentioned, I have the CV joints, just need to source an axle. Did any nissan car come with a solid 27 spline axle without any necking?

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Took a little bit of time to get some measurements. 

 

These are pertinent measurements to determine axle length that means from flange to flange so not including splined ends for these measurements.

 

280zx turbo adapter old welded modern motorsport ones

59mm with a 3mm outer lip, so a 56mm total length

 

Infiniti input shaft for R200

59mm from oil seal to flange

 

240z stub axle flange

36mm

 

280z input shaft for R200

19.4mm from oil seal to flange

 

1/2 shaft

15 3/8 inch fully compressed

 

1/2 shaft

16 1/2 inch fully extended

 

 

 

My car has parallel control arms the way it sits at the moment or right around there. It is also a 240z with an R200 so the 1/2 shafts definitely angle back.

As my car also sits low and I did not jack it up to change the geometry, these are as close to estimates as I could get with the car on the floor.

 

Driver side 1/2 shaft is at 16 1/8 inch

 

Passenger side 1/2 shaft is at 15 15/16 inch

 

Surprisingly not that much difference actually.

 

Based off of those numbers my total length I have to use for the passenger side is 15 15/16 + flange + r200 input - 280zx adapter - infiniti input equals ___

 

I'm waiting for my last spider joint and housing to come in to find out the final measurements, but basically I have to make sure that the axle can hit _____ inches with +- 0.5 inches or so which given that this conversion axle has two plunge joints really is not going to be a problem.

 

Once measurement is made I'm going to shoot off an e-mail to the axle people and see if they can shorten the path finder axle or if not it seems like they can make me a custom axle. 

Edited by seattlejester

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1/2 shaft

15 3/8 inch fully compressed

 

1/2 shaft

16 1/2 inch fully extended

 

 

My car has parallel control arms the way it sits at the moment or right around there. It is also a 240z with an R200 so the 1/2 shafts definitely angle back.

 

Driver side 1/2 shaft is at 16 1/8 inch

 

Passenger side 1/2 shaft is at 15 15/16 inch

 

johnc measured some half-shafts and posted on them a while ago.  Here's an excerpt from the Beta Motor Sports article he wrote.  I have a free yoke and if I add it's length (1.442" from flange surface to bearing cup hole) to his numbers, I get those shown.  He also got a difference of 7/8" side-to-side although his arms were at 7.5 degrees.  I think that you got your driver-passenger backward.

 

Driver: 12 .375" + (2*1.442) = 15.259 = 15 1/4"

Passenger: 13.25 + (2*1.442) = 16.134 = 16 1/8"

 

"In a R200 installtion, with the lower control arms about 7.5 degrees from parallel to the ground, the driver's side halfshaft's length is 12 3/8" while the passenger side halfshaft's length is 13 1/4". "

 

And, for an R200, the halfshafts should be essentially perpendicular to the hub, or parallel to each other.  It's the early 240Z with an R180 that has the diff mounted forward, and the shafts angled back

 

Just reference points.  I've wanted to work out the flange-to-flange distance when in the car anyway.  More numbers to work with.

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Regarding axle length:

 

Strangely enough what I have is what I measured as I did it in that order on a sheet of paper. That was a bit confusing on my end as well. I have read and seen differentials (R200 grows towards the driver side with mounting holes being the same) which would point to the driver side axle being shorter, but my measurements showed that they were pretty close if not the passenger side being actually shorter, I think I'm going to roll it up on ramps to get a better grasp though as I agree my numbers go against what all the reports say, and this was with a tape measure in the dark.

 

Regarding angled arms:

 

So that is also something that is strange, I definitely have a rearward rake the half shafts definitely lean back. When I did the swap I pulled the mustache bar from a 280z, compared to the R180 mustache bar it has a bit of a kink in it to move the differential back. My front bottom diff mount lines up with the bolt holes so I believe it is in the right place, but I know my RT top front diff mount I had to add a tab to bolt the bushing to, to make it fit, I recall asking the maker about it and he said that some early cars had the diff mount really pulled forward, but that his mount encompassed the others so I was just kind of left out of that equation. I've always believed that it was a latent problem with the early cars that was eventually fixed with the later cars (11/70 build date if I recall), although memory is fuzzy as to whether it was a 2+2 or a non 2+2 that I pulled the mustache bar from. As it looked, I even considered putting in the R180 mustache bar backwards as that would give more room then an R200 bar correctly installed. 

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I'm pretty sure I'm going to find I installed it backwards. 

 

That means my total axle measurement is moot at this point. I do know that the 280zx turbo axle seems to have about the same range so I'm still comfortable with the driver side. Passenger side on the other hand will need to be measured with the diff installed correctly or based off the numbers from John's article. I have plunge joints so quite a bit of variability so as long as I hit the middle of the range I should be fine. 

 

Based off the math I get for the passenger side I need...

 

16 1/8 inch for half shaft x 25.4mm / inch= 409.575 mm

19.4 mm for the input

36 mm for the stub axle flange

56mm for the 280zx adapter

59mm for the infiniti input

 

That brings me to 409.575 + 19 + 36 = 464.975 mm

 

464.975mm - 56 mm - 59mm = 349.975 mm

 

349.975 / 25.4 mm / inch = 13.7785 inches or ~13.8 inches. 

 

So I have to find the width of the sliding tripod bearings and how much space they occupy in the housings and find out the midpoint to calculate my axle length. Once that is done I can send off the measurements with the WD21 axle, best case scenario, they trim down the axle, respline it and I go on my happy way for about 70$. Worst case they have to build me a new axle with custom splines to my measurement, but that should be good for quite a bit of hp and I would think it would be cheaper then the price listed of 300$ as it is only going to be 1/3rd the size of their typical axle.

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