300zx (z31 and Z32) CV shaft flange bolt dimensions? Fun!

[bystickel]

My 510 has an open R200. I am determined to do an LSD on the cheap, and before I buy any kits or adapters, I intend to exhaust my MacGuyver options.

Looks like I have access to cheap Z31 (pre-'90)and ('90s)Z32 naturally-aspirated cars for VLSDs and CV shafts. Both have internals that will fit my long-nose housing.

I know that I'll have to shorten the axles.

What I need next is to find out the bolt circle diameters of the Z31's tripod and the Z32's 5-bolt set-up, so that I can determine if an adapter or modifications can be done to mate to my 4-bolt flanges.

Does anyone have access to this info? I have searched quite a bit and have not been able to find these dimensions. Thanks!

And, since every thread is better with pictures:

[JordanTr]

Nice looking bike frames!

I am also a MacGyverer and plan for a similar setup. I have a z31T LSD and z31T axles. They have the beefy "Birfield" CV joints which are much stronger than the tulip/tripod type joints. I plan on welding the late z31T bearing race into the 510 arm and using the early companion flanges to maximize the CV axle length. I am using the late z31T bearing race/brake bracket so that rear vented brakes will be a bolt on. Early Z31T had solid 5 lug rotors.



Jeffball610 and RWD_NissanMan have done this in the past.
My reasoning for all the hassle is that I want OEM CVs without using any fancy machined adaptors that require safety wiring etc... (as much as I love fancy machined bits... )

Read:
viewtopic.php?f=3&t=7060&hilit=z31&start=45
viewtopic.php?f=27&t=837&p=39808&hilit=z31#p39808

A couple things. Z31 axles cannot be shortened because there is no material to respline. If you do turn up some CV adaptors (and I'm sure you can!) then you'll be into it for another few hundred dollars for custom CVs--just a heads up. See pic, Z31T upper, WD21 lower.



I am hoping I will be able to make use of some short Nissan axles from a WD21 Pathfinder which share the same 27T spline as the z31T Birfield joints. Flipping the outer cage of the CV joint on the z31 axles warrants 3/8"/10mm per side as well.

Early z31T companion flanges are also 10mm shorter than their later counterparts since the late ('87-'89) cars had 20mm wider rear track. All Z31Ts use the same CV shafts except for the '88 SS which uses longer stubs in the diff to engage the viscous center. Other than that, the SS shafts are the same.

That's a long way of saying I don't really have any dimensions for you.

There is lots of reading about CV axles on HybridZ...

Good luck and let us know what route you go with!

[bystickel]

Jordan, thanks a lot for the links and the info. I've only been researching drivetrain compatibility for a couple of days, so I didn't understand everything you said, but am pleased that I did follow most of it (;

I don't have much hope of finding the Z31T parts around here, since so many others are wanting them, driving the prices up. I keep thinking that I'll find a way to make the 'commonplace' parts work. I'm hoping, anyway.

Before coming back to these forums, I thought my project was fairly high-powered, with just shy of 300hp. I can't see running any tire bigger than a 225/15, and I'm not planning a lot of clutch dumps. With that in mind, I was thinking that a Z31 NA or Z32 na axle would be fine, even if I end up cutting, sleeving, and welding them. I could be wrong.

I'm meeting a friend of a friend, tomorrow who has a Z32 na and a TT that he intends to combine into one good car, leaving good bits left over. He wants to retain the NA driveline, which would give me the TT shafts and 230 diff. Not good. I need to talk him into swapping to the 'good' stuff so that I can snag the lesser parts. I was just hoping to get a flange measurement off the NA flanges, ahead of time, so that I could make a wise purchase.

[bystickel]

Lots of views on the topic, but I guess this is as much of a mystery to everyone else, as well.

Edit: I went to look at the Z32 NA and TT cars. The owner intends to swap the TT motor to the NA chassis, but has no interest in swapping in the R230 diff and shafts. I couldn't get good measurements without removing parts. He'll sell me the 230 parts, which I have no use for.

I learned nothing that would help us find low-cost solutions. If you have the parts, please consider measuring them.

[heywier427]

Jordan,

any luck with this?

any chance someone who cut and welded z31t cv's took a measurement of the axel only?

it would be fantastic news if the pathfinder axels were short enough with the cages flipped.

what if they were close but you needed just a bit more. looks like you could weld on your own cage stops and machine in a new c clip groove as far down as you dare?

[JordanTr]

Not yet. Been busy with school. Don't anticipate I'll be sleeping much this week either....

In better days I made this excel sheet using numbers I found on hybridZ. I can double check the dimensions this weekend when I'm home.

Here is a pdf of Jordan's CV sheet.

Possibly machining the C clip grooves was my plan all along if I couldn't get the axles to work "out of the box". See a couple more detailed pics on my build.

Z31 upper, WD21 lower.


A few unknowns still need addressing:

How does 510 camber gain affect the CV axle length compared to the z31?

Where exactly does the sliding CV sit in the CV cage?

This whole setup is very promising to say the least. Just keep in mind that I plan to weld in the z31 bearing races into the 510 arms...

Thanks for the response!

[heywier427]

it all does look very good

im a year or so away from beginning my build, but im just trying to get my ducks lined up!

a newb question here... the z31t cv's has one diff shaft much longer than the other, but my r200 half shafts are only different by a half inch or so. im guessing that extra length is to engage the lsd? (my diff came open/not lsd)

I am going helix in my diff, so would I need the longer shaft, or both of them to be short? ie buy 2 lefts or vise versa.

As far as you welding your bearing races in, would that have any affect on axle length for me (or others not going 5 lug)?

Would you be welding your races in where these stock (wd21 hybrids) axles would for (you). Or would you be welding them in at stock location, and figuring axle length/compatibility from there?

Thanks. I wish I could be more help, but our garage is full all the time! We plan to stop taking work for a whole year to block out some "me" time!

keep up the good figuring!

[JordanTr]

a newb question here... the z31t cv's has one diff shaft much longer than the other, but my r200 half shafts are only different by a half inch or so. im guessing that extra length is to engage the lsd? (my diff came open/not lsd)

I am going helix in my diff, so would I need the longer shaft, or both of them to be short? ie buy 2 lefts or vise versa.

Mine are from an '88 Turbo Shiro Special which had the unfortunate viscous LSD. You are correct, the long stub axle is to engage the viscous center. All other turbos from any year use very close to equal length stub axles whether or not they had the clutch pack LSD (my understanding).

I debated going Torsen etc but I ended up finding the stock LSD for very cheap (albeit viscous). If I get sick of the viscous and decide to get an S15 helical, 1.5 way or 2 way it will bolt in provided I can source a pair of stub axles from a z31T that is not a Shiro Special.

As far as you welding your bearing races in, would that have any affect on axle length for me (or others not going 5 lug)?

Would you be welding your races in where these stock (wd21 hybrids) axles would for (you). Or would you be welding them in at stock location, and figuring axle length/compatibility from there?

I am not sure if the 4 lug stub axles from z31 NA's would mate to the turbo companion flanges? That wasn't in the scope of my research.

For me, I have very tight wheel fitment so I plan to jig my control arms up for welding so that the wheel mounting face doesn't move at all.
You could obviously change the bearing race placement to suit balla dish or Honda offsets but I like my GTRs and they fit great as is. Drastic changes inward obviously wouldn't work well with the CV axles that are already at their limit of shortness.

[heywier427]

I am not sure if the 4 lug stub axles from z31 NA's would mate to the turbo companion flanges? That wasn't in the scope of my research.

I would be using the ends of the turbo axles and hopefully using the centers of the wd21's.

in any event, just read your entire build thread. nice

I will be following your progress on rack as well.

Thanks.

[JordanTr]

In any event, just read your entire build thread. nice

Thanks, There's still a long way to go... haha.

I would be using the ends of the turbo axles and hopefully using the centers of the wd21's.

If you don't plan to get a viscous center, be sure to get z31T axles from anything but the 1988 Shiro Specials. Alternatively, you could search for Shiro diff stub axles and run a cheap viscous center from an s13. (I have checked that this fits and engages LSD). Again it comes down to good or cheap..

Anyways, car stuff is more interesting than homework so I found this which makes it sound like 5 lug to 4 lug would simply be a stub axle and bearing swap. It sounds like the turbo companion flange would bolt on.

Picture of early(short) vs late companion flanges (b/t outer CV and stub axle) for reference


Normal z31T axles look like this with or without the cLSD (from what I understand)