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New source for CV axle conversions?

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So I'm a little embarrassed here, but I came across what I think is a new source of CV axles the other day.  Has anyone else seen/used these before?

 

https://datsunrestomods.com/collections/all

 

They offer some pretty nice bolt-in CV conversions for both stock R180 and Subaru R180, and their prices seem better than most other vendors.  The one obvious downside is the recommended torque limit of 225 ft-lb (possibly because they're using stock Subaru cv joints?)

 

I've contacted the vendor via email to gather some technical background, and may very well be ordering a pair for myself.  Would be interested to hear if anyone else here has information or personal experience with this company.

Thanks! 

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Looks like he just swaps flanges.  I wonder if he is just cutting flanges off old u-joint axles and welding them on to "CV" axles.  I can't remember all of the different types, but I think those are "tripod" axle ends.  Not "real" constant velocity joints.

 

I would want to know how he aligns the flanges before welding to be sure that they're centered correctly.  He advertises smoother operation but it won't be smooth if there's any misalignment.  He also says that the axles are "sourceable" but he must mean the center piece/shaft.  The housings, with flanges, are going to be one-off pieces, available only from him.

 

Nice find, interesting product.  Not sure that they're much better than a u-joint axle though.  What's the benefit?

 

image.thumb.png.6f9e026b3bd751dad191f74057cf1a66.png

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Yeah, I have the same questions. 

 

I made the decision a while ago to switch to CVs once my half-shafts started crapping out.  After 5 years of problem-free race-use, I'm still waiting for that to happen (but I'm only making moderate power, so it may still be a while).

 

Still nice to see new products being introduced for our 45 year old vehicles!

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I wonder where the came up with the torque limit. Breaking welds? Doesn't seem likely since guys are running Z31T CV adapters welded to stock companion flanges. Maybe they're using particularly weak CVs. Maybe they're just under-rating them.

In a 510 the U-Joint angularity can be a really serious issue. Haven't heard anyone having problems with Zs in that respect. I think the issue is the semi-trailing arm rear suspension and the ride height that 510 people tend to want. 

Being that the stub axle is such a weak spot in the Z, I'm not inclined towards anything that doesn't address that issue. Still think the modern-motorsports.com chromoly stubs and companion flanges are a good answer, and I like the Z31T CVs. If that's not enough the full chromoly setup with 930 joints and stubs for the diff and wheel ends from modern-motorsports.com is as good as you're going to get for an R200. Still blowing that up? You're going to need bigger axles, that means F8.8 and some kluged together stub axle for the wheel end, at which point why not SLA and change the shocks and the brakes and then while you're at it...

Edited by JMortensen

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Was thinking along those same lines, Jon; so I contacted the owner to get more info, and received a really fast/comprehensive response to my email.  Copy of text included below FYI....

----------------------------------------------------------------

John Meyer

9:58 AM (9 hours ago)
 
 
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to fritz
Hello Fritz-
Someone referred me to your company the other day as a new source for CV axles, and I have to say I'm impressed with your product line!  
 
I'm currently running an Sti R180 in my 240Z, and I already have aftermarket machined side axles, so I would primarily be interested in your "CV axle set - Datsuns with stock differential".  Can you tell me which CV joints are used in those axles?  Are they OEM Subaru CV joints?  And if so, is that the source of the recommended torque limit of 225 ft-lb?  Just curious....
 
I had previously planned to fabricate my own CV axles using 930 CV joints; but I'm always looking for new options, so I may very well be contacting you to order a set of yours.  Is there a long lead time for these units once they're ordered?
 
Thanks very much, and I wish you the best of luck.  They look to be very nicely assembled units!
r/John Meyer
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Datsun RestoMODS

10:47 AM (8 hours ago)
 
 
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Hi John, 
 
Glad to see you liked what you say and the fact that you were referenced here. 
 
The CVs are not Subaru. I'd rather keep the R&D quiet for now but I can say that these axles have larger housings than the STI and the axle diameter is also ~1/16th thicker. These CVs are beefy and although I've listed the OEM 225ft/lbs limit (more to keep anyone from trying stupid stuff that would break just about anything) I will be mounting them on my VQ37VHR 280z when it's complete. I have several customers with close to 300 ft/lbs engines as well. 
 
Finally, the CVs are brand new, the highest quality I can source. The axles are not cut or resplined, modifications are exclusive to the housings. 
 
The goal for this business is to give back to the Datsun community. I do have a well paying day job so the axles are priced to cover costs and provide just enough cushion for R&D on new & unique products (wait until you see what's coming down the pipe!). 
 
As a result, it's been flat out building CVs - pretty much the reason why marketing has been minimal in the S30 community right now. I'm unable to build any surplus stock, a good problem I guess. 
 
My suggestion would be to place an order as soon as you're ready. Anything ordered today will be shipping early the week of February 11th. 
 
Sorry for the long reply, I like potential customers to have full transparency. Please don't hesitate to contact me if you have any other questions. 
 
Fritz
 

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I noticed some traffic on my web site from HybridZ and was pleasantly surprised to see a thread opened on the CV axles. Thanks John!

 

Mods, I'm new to this 'vendor' role, please let me know if I'm breaking procedures etc...

 

I'll keep this theme to simply answering some of the questions raised above. Please don't hesitate to add questions and I'll continue to answer as best as I can - w/o giving up too much R&D. ;-) 

 

  • "...he seems to be quite a regular in the "Dime" community" - that I am. For the past 7 years I've been a proud owner of a 1972 Datsun 510 2 door, orange. I also own a 1976 280z that currently being built up into another fun toy and R&D test bed for future products. Much of my involvement on 'The Realm' has been sharing in my experimentation (Yamaha R1 carbs on a KA24e and MegaJolt EDIS ignition etc...) and learnings.
  • "..I wonder if he is just cutting flanges off old u-joint axles and welding them on to "CV" axles..." - nope. I manufacture brand new adapters/flanges, accurate up to 4 thousands of an inch on centering/mounting to make them dead smooth. The flange's bolt-hole placement is left to CNC machining for repeatable accuracy.
  • "...Not sure that they're much better than a u-joint axle though.  What's the benefit?" - Several benefits:
    • As the U-joints in our axles fail, finding replacements has been difficult, at least for me.
    • Also, with lowered Datsuns, the larger angles within the axle exaggerates a U joint's inability to rotate at a constant speed. These newer CV axles (short for Constant Velocity), can rotate at more consistent speeds with larger angles. The end result is a noticeably smoother ride - even for Datsuns with seemingly fine  stock axles. Another reputed benefit is more drivetrain efficiency and a couple percent increase power to the wheels.
  • "I wonder where the came up with the torque limit. Breaking welds? " :
    • A LOT of engineering went into these CVs - down to shear calculations, metals selected for the adapters and how it interfaces with the CV, impacts from tempering, redundancy in fastening etc... Calculations showed that the fastening/welding technique is ~20-30% higher than the stubs at their weakest point.
    • Back to the question, the torque limit was placed because that's the approximate OEM limit that the axle is designed for, and I wanted to limit anyone trying these axles on over the top machines.
    • As previously posted the axles are comparable to the Subaru STI which are quite capable. My guess on the weakest link now lies in either the axle splines or the shoulder/D bolts themselves.
  • Being that the stub axle is such a weak spot..." - I'm not sure where on the stub you are referring to but I do offer an integrated stub CV where an OEM STI stub is directly fastened onto the CV housing - in 3 different manners (it's NOT coming off!). It's really slick with only 4 bolts to fasten the axle onto a clip-in diff setup. A similar R200 version is in the plans for this spring as well. 

 

I hope that answers the questions.

 

My CV axles are designed to fill a niche market and not directly compete with existing products/vendors. There are already several options for owners with massive HP and/or heavy track duty needs. My CVs, and frankly the basis of all my future products, are intended to be an affordable & original solution that offers a level of reliability (read: lack of maintenance) you expect from a street car, be it stock or with a moderate swap/upgrade powerplant.

Edited by Datsun Restomods
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3 hours ago, Datsun Restomods said:
  • "..I wonder if he is just cutting flanges off old u-joint axles and welding them on to "CV" axles..." - nope. I manufacture brand new adapters/flanges, accurate up to 4 thousands of an inch on centering/mounting to make them dead smooth. The flange's bolt-hole placement is left to CNC machining for repeatable accuracy.
  • "...Not sure that they're much better than a u-joint axle though.  What's the benefit?" - Several benefits:
    • As the U-joints in our axles fail, finding replacements has been difficult, at least for me.
    • Also, with lowered Datsuns, the larger angles within the axle exaggerates a U joint's inability to rotate at a constant speed. These newer CV axles (short for Constant Velocity), can rotate at more consistent speeds with larger angles. The end result is a noticeably smoother ride - even for Datsuns with seemingly fine  stock axles. Another reputed benefit is more drivetrain efficiency and a couple percent increase power to the wheels.

 

They look like a neat new product.  There will eventually be a limited source of replacements for the u-joint half shafts, for sure.  So that's a good reason.

 

I have a lowered 280Z and the halfshaft actually has a lower joint angle.  It's almost straight.  So that reason doesn't fit.

 

I'd suggest not over-hyping, and being sure about your claims.  The 800 or 1000 HP claims by the other guys get ridiculed all the time.  At the end of the day, it's just a CV axle replacement for u-joint half-shafts.  Might be a lot of effort behind, but still, it's just a CV axle.  And, from your other Dime thread there's not enough of them installed to make a good claim about smoothness.  The u-joint shafts are very smooth if the u-joints are in good shape.  Just saying, time and experience will tell, today's words don't mean too much.  I don't think any have been installed in a Z yet, have they?  Can't really make Z claims until they've been in a Z.

 

But, it's very nice that no adapters are required.  It's a true "bolt-in" replacement.  That's your real selling point.  If you tell where the CV's come from it will add a lot.  Are they made in Asia knockoff cheap-o's or high quality name brand car parts.  Some of the Porsche 930 style shafts use cheap joints and now they have a bad rep, depending on where you get them.

 

Good luck.  Show some installed in a Z.

 

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Welcome to the forums!

 

Glad you understand your market, and I'm sure it is a welcome addition.

 

As long as you don't try and sell outside the vendor section, or respond to every post looking for axles with a link to your site this kind of discussion is exactly what I personally like to see.

 

I will have to agree, I have seen some Z's with upward angles, but they would be at chassis scraping status at that point, maybe a point for Z's would be with the tripod joint on the outer end you get away from potential binding with R200's that the axles face which you are addressing with the "short" offering. CV's have a smoothness that is slightly apparent in my limited experience. Not huge, but I can sometimes notice when I get in other Z's with the stock axle, granted as mentioned they could just be worn ujoints compared to brand new CV's. 

 

One point I ran into when talking about STI axles when I had an STI diff, is that keep in mind the power was sent to all 4 wheels in these cars, on drift subaru's they definitely have to undergo upgrades as the axles don't seem to hold much power. If this is a stock offering, I imagine it would be from one of two cars and both are of this type of setup, and it seems that you are addressing this with the low stated power numbers.

 

Just as a warning, we as a community tend to be pretty scrutinizing, please do not take offense, maybe view it as an area that could use improvement to put future customers at ease!

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Thanks for the welcome and the heads-up on community vibe.

 

Honestly, my 'home' Datsun forum 'The510Realm' can also have some passionate members. I'm fine with respectful scrutiny as it's often just a 'why' or 'prove' question which is the basis of Critical Thinking and how we eventually engineer improvements - and the birth of these axles to be honest. The 510Realm thread that John linked to above was my coming out party, and the goal was to bring these CVs to the community Datsun gurus to scrutinize to death. Trusted members were given more in-depth engineering background and their subsequent honest opinions is posted for all to see.

 

CV vs U-Joint is sort of like Fuel injection vs carb IMO. I nicely tuned carb setup runs pretty damn good and it's only 'disadvantage' to Fuel Injection is overall refinement (weather, startup, MPG). Both setups can run well and offer a specific experience. If a customer is looking for additional smoothness/refinement (basis for Restomoding), then any CV is a viable consideration.

 

My 'business model' is a little unique, as previously mentioned DatsunRestomods is not my livelihood/source of secondary income, nor do I need it to be. This is my way to give back to the Datsun community and to fulfill a craving to create out-of-the-box solutions (and there's some good ones coming up IMO).

 

The scope of my 'selling' will be limited to the vendor section. I'll post a thread there when ready along with pics of S30 installs - several are out there already. ;-)  

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Love what you've done here! Axle setups are few and far between, and we need all the options we can get. I'm in a similar situation in that I make the weld-on Z31T flanges for sale mainly on DPAN, but here as well. I too make them just for the hobby of it. However, my part really is not an ideal solution, as finding old OEM axles is becoming more and more difficult. Keep up the good work and we look forward to seeing what you come up with.

If what you have was available when i started, i'd have sourced a $400 STI diff, and $880 set of your plug in axles and be done with it. Plug and play.

My 3.90 R200 was $250, LSD was $500, Axles were $250, making custom flanges was at least $250, having them welded another $100.  That's $1350 and still doesn't include new mustache bar, and the labour to setup the diff, etc etc.

 

Are the Plug-in STI style axles welded on the splined side as well? any possibility of using an OE type STI end there?

 

 

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12 hours ago, mtnickel said:

Are the Plug-in STI style axles welded on the splined side as well? any possibility of using an OE type STI end there?

 

Thanks for the feedback!

 

'Plug and play' is definitely the goal here. Re-engineer as little as possible. Good news is that the STI diffs are getting cheaper. They've gone down a couple hundred from when I sourced one for my 510 a few years ago. I'd run the same setup for my 280z but I'm working on a potential R200 solution instead.

 

If I understand your question, the OEM STI inner housing is not swap-compatible with the axle I source.  I tried several ideas with no luck.

 

The R180 STI stubs are welded onto the CV housing in 3 different locations. One weld along the entire perimeter of the stub's flange, three .4" plug welds through the flange into recessed pockets within the housing,  and finally one large plug weld on the underside of the flange through the center of the housing. It's not coming off. 

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