75 280 Rear Suspension Work & Disc Brake Conversion (MilkFab)

[Zed Head]

If the supplier doesn't know then they'll just keep disappointing customers.  One of those weird ironies where exposing flaws helps the company.  You've already said, in essence, that the Silvermine product(s) (undefined) has/have problems.  Sorry, it's just the logic of the situation.  Not sure that "on notice" is the correct term here.  You might find that it really was you, not them.  But, without the story it looks like them.

[Yarb]

I was not saying it was a Silvermine problem. Surely there are a lot of folks that had success. As I mentioned earlier in the post I had an issue with binding. Could have been the axles who knows. What they produce, fit and function were fine.

[Zed Head]

Sorry, I misunderstood.  You're saying it's a Trakmotive problem.  But don't the Trakmotive axles come with the Silvermine kit?  I don't know.

 

[HusseinHolland]

12 hours ago, Captain Obvious said:

I've never messed around with converting to the CV axles, so I'm all kinds of confused. With that in mind...

You cut length off the end of the stub axle. And now (with just the washer and nut) on the threaded portion of the stub, the end of the axle is below the surface of the nut? How does it look with everything assembled in-situ? The reason I ask is that when installed "as used" the nut will not thread on as far as you have in your pics and you will have even less thread engagement. I'm not really worried that you'll have enough threads, but I am a little concerned that there won't be any place to put your anti-vibration peen.

In other words... When you put everything together, it's the bearings and spacer tube (distance piece) that establish where that nut will get tight. Not where the washer bottoms out on the splines like you have in your photo. The nut will become tight before it's as far on as you have it in your pics.

Another question is how do the new CV adapter flanges attach to the original rectangular flanges? I've never messed with them, so I have no idea. Do you drill holes for bolts, or do you weld them on or what?

And lastly. it should be a relatively simple matter of machining the original wheel mounting flange to accommodate some sort of hub-centric ring. I haven't done it, but seems like you could turn down the original center hub to a smaller diameter and fit a special made centering ring over it. Press it on with no welding required?

What is the diameter of the original hub ring, and what diameter are you trying to achieve?

 

Stub assembled with bearings, sleeve, inner flange, washer & nut. I enlarged the ID of the old bearings so I could do this test without needing a puller for more than the inner flange.

I can flats to the stub, to allow it to be peined in place. I'll need to cut 3mm off the nut, so the flange will be minimal. I guess I can also loctite the nut instead of flying on the pein. 

Alternatively, I leave the lip as is, and remove the CV cup cover. 

16mm from washer to outside of flange. Nut is 19mm. Torquing the nut may reduce the height by a mm, I suppose.

The CV adaptor gets welded to the old flange. As I stated above, the problem with the design is that I loose 8mm off the travel of the CV shaft, hence my desire to re-work it so that the modified flange sits at the same depth as the stock flange (35mm off the back side of the dust cover)

For the hub-centric rings, I'm going to have the existing nubs shouldered so the sleeves sit concentrically outside them. The rings cannot be more than 12mm deep.

centering rings cut from used Volvo hubs - OD matches OD of existing Datsun flange (63mm), so no issues with fitting the rotors

EDIT: not sure why the site is duplicating images - it won't allow me to delete this one, either

Edited July 11, 2023 by HusseinHolland

[HusseinHolland]

8 hours ago, Zed Head said:

Not sure if you mentioned the Silvermine package in one of your threads (it's hard to to follow along when you start a new thread for each sub-project), but if it's one with adjustable control arms you could also widen the track to get clearance for the axles.  That's what some people do.  

And, since I'm here, might as well say that the u-joint halfshafts are actually pretty strong,  Lots of guys run them with high HP Chevy small blocks.  The CV axle swap was a neat idea when people were using Nissan CV axles but I'm not so sure that aftermarket Trakmotive axles are better than Nissan u-joint halfshafts.  Not trying to be a buzzkill, just pointing out the aftermarket problem.  That is also something to keep in mind if you run the u-joint shafts for a while.  New aftermarket u-joints are probably not better than used Nissan u-joints.

Anyway, looks like fun.  

I posted separate work threads in the appropriate forums, I assumed that was the correct approach for the site. I didn't see where the build thread category was hidden until GrannyNot asked if I had one...

I'm not using aftermarket control arms. The whole point of modifying the flange setup from the way Silvermine supplied it (loosing 8mm depth) is to avoid the binding that can occur (supposedly only with lowered cars). I've communicated with him by email regarding changes to his design, but he wasn't too helpful. My car already has 250K miles, I don't really want to keep the stock shafts for when I do the VQ35DE conversion. I'd rather deal with it now than later. 

Edited July 11, 2023 by HusseinHolland

[HusseinHolland]

4 hours ago, Zed Head said:

Sorry, I misunderstood.  You're saying it's a Trakmotive problem.  But don't the Trakmotive axles come with the Silvermine kit?  I don't know.

 

The Trakmotive axles do come with the Silvermine kit, I asked him that when I ordered the flanges. He said the binding issue is with cars lowered more than 1"

Edited July 11, 2023 by HusseinHolland

[Zed Head]

JMortensen had a good suggestion over on Hybridz, years ago.  He assembles his suspension without the spring and runs the hub through its full travel by hand.  Might be worth doing to verify the problem

Also note that for a reason that has not been quantified, the 240Z's tend to have binding problems with the factory u-joint shafts after an R200 swap.  The only rational reason would be that the 240Z flanges project in toward the center of the car (less distance between flanges left to right) than on the 280Z's.  In short, it might be worth confirming it's a 280Z problem and not just a 240Z problem.

On the nut - you could tack it down with a MIG welder if you have one.  It's easily accessible to grind off in the future.  200,000 miles from now.

[Zed Head]

20 minutes ago, HusseinHolland said:

I posted separate work threads in the appropriate forums, I assumed that was the correct approach for the site. I didn't see where the build thread category was hidden until GrannyNot asked if I had one...

My point was just that I didn't know when "Silvermine" was introduced to the work.  It appeared with no previous mention.

They have a lot of stuff.  Couldn't tell what you were working with.

https://www.silverminemotors.com/collections/datsun-280z

[HusseinHolland]

38 minutes ago, Zed Head said:

My point was just that I didn't know when "Silvermine" was introduced to the work.  It appeared with no previous mention.

They have a lot of stuff.  Couldn't tell what you were working with.

https://www.silverminemotors.com/collections/datsun-280z

"On the nut - you could tack it down with a MIG welder if you have one.  It's easily accessible to grind off in the future.  200,000 miles from now."

I think I mentioned it last week, but not specific to Silvermine. The pics above clearly show the Silvermine flange design  - they cut the inside to a depth of 4mm to allow the stock flange to sit that far in. Still means 8mm depth is lost for the new CV shaft. I want the flange set to the same depth as the stock one. Haven't found a thread that gives the exact length of the stock driveshaft compared to the 300ZX T axles.

Good idea on tacking the nut. I've been reading the thread he laid out - there are a lot of conflicting posts within it - ppl using custom axles, 300ZX NA axles, etc., etc.

Edited July 11, 2023 by HusseinHolland

[Captain Obvious]

50 minutes ago, HusseinHolland said:

I can flats to the stub, to allow it to be peined in place. I'll need to cut 3mm off the nut, so the flange will be minimal. I guess I can also loctite the nut instead of flying on the pein.

The CV adaptor gets welded to the old flange. As I stated above, the problem with the design is that I loose 8mm off the travel of the CV shaft, hence my desire to re-work it so that the modified flange sits at the same depth as the stock flange (35mm off the back side of the dust cover)

For the hub-centric rings, I'm going to have the existing nubs shouldered so the sleeves sit concentrically outside them. The rings cannot be more than 12mm deep.

I'm not sure I would trust loctite there, even the red stuff. If that nut comes loose, you could lose a wheel. Highly unlikely, but just not sure I would trust a loctite bond and ONLY a loctite bond.

So I've done rear wheel bearings a couple times and I've switched over to the newer style of deformed thread nuts they used on the 280ZX cars. I'm not sure how the thickness of the newer ones compares to the older ones, but if it's thin enough and the deformed threads are down far enough, they could be a simple solution.

The newer nut looks like this. Photo credit @ Blue:

[HusseinHolland]

7 minutes ago, Captain Obvious said:

I'm not sure I would trust loctite there, even the red stuff. If that nut comes loose, you could lose a wheel. Highly unlikely, but just not sure I would trust a loctite bond and ONLY a loctite bond.

So I've done rear wheel bearings a couple times and I've switched over to the newer style of deformed thread nuts they used on the 280ZX cars. I'm not sure how the thickness of the newer ones compares to the older ones, but if it's thin enough and the deformed threads are down far enough, they could be a simple solution.
 

I'll see if my local Nissan dealer can get them - or even better, has them. 43262-W1200 - about $6 . The stock ones are 19mm deep, standard flanged locknuts should be shallower, so thanks for the suggestion. Worst case, I can tack the new nuts with my MIG after they are torqued.

[Yarb]

To clarify, My setup is a R200 LSD with BC Coil over shocks. Everybody’s setup will vary at some point.