Grafting a C5 rear suspension on C3

...A while back I had some axles shortened and balanced. This was at a driveline shop that primarily does trucks. However, the guy I talked to had lots of experience with car stuff. I was talking to him and he pretty much told me that anything was possible as far as adapting and converting. And all done with catalog items.

You might wan't to find a driveline shop close to you and show them what you are after.

Roger That! I'm trying to do some homework and get ideas before I sound too stupid at the local shop. There's one a mile away and my engine builder is a few blocks and an excellent machinist.

Looks like you have done way more homework on this than I have but, I seem to recall, you can pull the inner CV joint off the stub axle and buy a splined yoke for the u-joint. Presumably that is welded on to the axle stub.

Sound like that could be the easiest solution, but would be a mix and match of CV (outer) and U-Joint (inner) on the half shaft.
Originally posted by rtj
... I don't think you want to mix unjoints with cv joints. U joints have a cyclic torque output unless at 0 degs. That's why ujoints are supposed to have similar angles at each end.
-- but I have not found any reference to that yet, anyone else have thoughts on this issue?


Ahh - but it just occurred to me - I'd loose the compression aspect of the inner CV joint... hmm back to the garage with another cuppa...

Thanks! Jim
 
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Closing the loop (as it were) this from a GT40 Forum -
http://www.gt40s.com/forum/gt40-tec.../24205-half-shafts-u-joints-vs-cv-joints.html

Jac Mac... If you use only one U-Joint with a CV at the other end you introduce an acceleration/deceleration in rotational speed into the driveline at any time the U-Joint is not running dead straight. If two U-Joints are used & correctly phased the acceleration/deceleration is mainly confined to the shaft area between the U-joints and it depends on the amount of material & diameter involved in that portion of the shaft how much it will be felt by you ,the driver.( I say mainly since if the angle in each U-Joint is not the same then the rotational speed change for each joint will be different)

Now as an example if you have a U-joint @ the Transaxle & a CV @ the hub carrier the half shaft/axle/wheel will try to accelerate/decelerate when the U-joint assumes any angle.

Thanks rtj for the input - I'm smarter now...Thanks Google!

Looks/sounds like it may be the "Jeep-Style" option of a U-Joint welded to the housing of the C5 shaft (no CV) and use my slip shafts.

Now to see if parts are available -- and they fit! Ahhh.. ain't hot-rodding fun?!

Cheers - Jim
 
I think the off road guys get away with mixing cv's and ujoints is
because the over build the driveline.
 
Splined Shaft Manufacturers - ANY Recommendations?

I've found a solution! But now need some help - "executing it."

So far, I've been all over the internet this past several weeks, and many sources in India, China, and Tiawan. I spoke with VanSteel, they have a semi-retired machinist that does their C3 output shafts and hardens them. Tom of course is a great resource for all things "differential" – but currently swamped. GTR1999 (Gary) gets his from Tom…

I need to source someone to cold roll a couple of splined shafts for me (preferably 4130/4140), then heat treat.
(Unless there is a good reason to not Cold Roll – and just opt for a machined splined shaft then heat treat?)
Here is a pic of the desired end result (not to scale):

126953dcd17acf5ef.jpg

These will be used in my C3 rear differential, so the inside, up to and through the case, looks normal with seventeen splines and a C-Clip. Then, the outside is to mate to a C5 CV half shaft, 41 splines and a retaining clip. Because these are mounting to a "standard" C3 differential, they will be the same overall length; unlike the C5 and C6 output shafts (driver's side is longer than passenger's).

I'm looking for recommendations/suggestions any of you might have.
There are a couple of firms, I have found on the web, but am waiting to hear if they'd participate, and have no experience with any of them..
http://traceygear.com/english/Products/Spline.html (Rhode Island)
http://www.grobinc.com/coldrolled/cust_spline_shafts.htm (Wisconsin)
http://www.true-gear.com/services.html (Ontario)
http://www.usaxle.com/splining.html (Pennsylvania)
http://www.team-ind.com/manufacturing/splines (North Carolina & Minnesota)
http://www.ashleyward.com/spline-rolling-thread-rolling-services.html (Indiana & Ohio)
http://www.cvaxles.com/ (Florida)

Currently, new C5 half shafts can be purchased relatively inexpensively (although made in China, I expect they will be more than adequate). C5 Racing SKF bearing prices are coming down and should give a solid season of racing. Sourcing and preparing the C5 uprights is "no problem", but some machining and Hobby Shopping required for a full on double wishbone setup. Coil-Overs can be set up with pushrods – or direct mount to cage/chassis rear stub. Toe-In control is easily fabricated.

The only challenge remaining to completing the C5 IRS mating to a C3 Chassis – getting the drive line connected!
Help?:sos:​

Thanks in advance
Cheers - Jim
 
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I've found a solution! But now need some help - "executing it."

So far, I've been all over the internet this past several weeks, and many sources in India, China, and Tiawan. I spoke with VanSteel, they have a semi-retired machinist that does their C3 output shafts and hardens them. Tom of course is a great resource for all things "differential" – but currently swamped. GTR1999 (Gary) gets his from Tom…

I need to source someone to cold roll a couple of splined shafts for me (preferably 4130/4140), then heat treat.
(Unless there is a good reason to not Cold Roll – and just opt for a machined splined shaft then heat treat?)
Here is a pic of the desired end result (not to scale):

126953dcd17acf5ef.jpg

These will be used in my C3 rear differential, so the inside, up to and through the case, looks normal with seventeen splines and a C-Clip. Then, the outside is to mate to a C5 CV half shaft, 41 splines and a retaining clip. Because these are mounting to a "standard" C3 differential, they will be the same overall length; unlike the C5 and C6 output shafts (driver's side is longer than passenger's).

I'm looking for recommendations/suggestions any of you might have.
There are a couple of firms, I have found on the web, but am waiting to hear if they'd participate, and have no experience with any of them..
http://traceygear.com/english/Products/Spline.html (Rhode Island)
http://www.grobinc.com/coldrolled/cust_spline_shafts.htm (Wisconsin)
http://www.true-gear.com/services.html (Ontario)
http://www.usaxle.com/splining.html (Pennsylvania)
http://www.team-ind.com/manufacturing/splines (North Carolina & Minnesota)
http://www.ashleyward.com/spline-rolling-thread-rolling-services.html (Indiana & Ohio)
http://www.cvaxles.com/ (Florida)

Currently, new C5 half shafts can be purchased relatively inexpensively (although made in China, I expect they will be more than adequate). C5 Racing SKF bearing prices are coming down and should give a solid season of racing. Sourcing and preparing the C5 uprights is "no problem", but some machining and Hobby Shopping required for a full on double wishbone setup. Coil-Overs can be set up with pushrods – or direct mount to cage/chassis rear stub. Toe-In control is easily fabricated.

The only challenge remaining to completing the C5 IRS mating to a C3 Chassis – getting the drive line connected!
Help?:sos:​

Thanks in advance
Cheers - Jim


Did you try talking to Curie, Strange, Moser etc ? They may have a contact for one of a kind pieces. Plus, if you can find an appropriate axle to start, you are half done. Just cut more splines on one side.
 
Hayes couplings? Just a google hit.

"If you have a custom shaft application and are having troubles finding a supplier, you've come to the right place. We make custom shafts of all types: SAE, non-SAE, splined, keyed, flanged, internal splines, external splines; you name it."
 
Any C5 owners here upgraded their Differential Shafts?

Just wondering if anyone has upgraded their C5 differential and has the old (replaced) C5 output shafts laying around? I'd like (either side) to measure for building an output shaft for my C3 diff. The external splines are the ones I'm interested in.

126953de3bf176a59.jpg

I have a spare C3 output shaft to use as the example for the internal side.

126953d6709b62d87.jpg

Having a part in hand makes it easier to show machinists what is needed. And easier to measure for a sketch.

PM me here and let's see what we can work out.


Thanks - Jim
 
Jim,

Have you looked at using Tom's inner axles -- they have a large flat flange on the outboard end -- and see if you can drill and tap the flange for the six bolts that hold a Porsche 930 CV joint? The 930 joint is 28 spline. Then use the C5 outer CV. You might even be able to cut a C5 axle shaft and have the inboard end re-splined for the 930 CV. If not, I highly recommend The Driveshaft Shop to build the axles. I think I posted pictures of my brother's 120 Jag with the C6 suspension (control arms and uprights) and a 2010 Camaro differential. The Drivehaft Shop built custom axles that had inner splines for the Camaro rear end and a C6 outer end. Fit perfect and their service was excellent. For a little more money, I'm sure they could build the entire affair -- inner end splined for the C-3 carrier, axle shaft, and outer set up for the C5 parts. They do this kind of stuff all the time.

Pappy

Jim, click on my photos in the upper right of this post -- I uploaded a shot of the Jag's rear with the C6 control arms and the Drive Shaft Shop axles, in case it's any help.
 
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Jim,

Have you looked at using Tom's inner axles -- they have a large flat flange on the outboard end -- and see if you can drill and tap the flange for the six bolts that hold a Porsche 930 CV joint? The 930 joint is 28 spline. Then use the C5 outer CV.
Pappy-
Yeah, saw something like that done on one of the "Subie" sites. Then I'd be stuck getting some 930 shafts...

You might even be able to cut a C5 axle shaft and have the inboard end re-splined for the 930 CV.
That is kinda where I was going earlier with the U-Joint mods. Seemed like a lot of issues to sort out.


If not, I highly recommend The Driveshaft Shop to build the axles. ... Fit perfect and their service was excellent. For a little more money, I'm sure they could build the entire affair -- inner end splined for the C-3 carrier, axle shaft, and outer set up for the C5 parts. They do this kind of stuff all the time.

Well, the solution is slowly coming into focus for the driveline. I am now the proud owner of 2 brand new C5 CV half shafts.
Now, all that remains is to mate the diff to the inner C5 CV. I'll be getting quotes on short run of a couple of shaft stubs, C3 Diff splines on the "inside end of stub" and C5-CV splines on "outside".

Driveshaft Shop is on my short list. Tom was first, but too busy just now. I am waiting on getting a sample of the C5 drive stub (the left long one in the pic above) to have for reverse engineering. I have a spare C3 drive stub sitting next to my keyboard.

I'll report back and fill in the details as I make progress.

Cheers and Thanks to all - Jim

BTW - seems like years back TT recommended going down the Jag route. Just looking at the eBay - you can get complete rear ends off XJS/8 for under $500. Still have the half shaft as a UCA, but eliminates the toe situation of the C3 IRS.
 
Have you seen these? Denny's driveshafts.

Flange Yoke 1350 Series. Mounts to any GM Double Cardan CV style transfer case flange or rear end flange. Use this flange yoke to eliminate the Double Cardan CV on Chevy and GMC 4x4 front driveshafts. Also can be used to eliminate the Double Cardan CV when using a rear end that originally had the need for a CV Joint.
 
Thanks for that - I think I'm on another vector right now.
I've got 2 complete - new- C5 CV half shafts. So that means the bearing, hub, and wheel situation is resolved. Now to mate the inside (diff) to the CV Half Shaft. If I had the flanged output shafts on my diff I could kinda go that route. But have ordered 2 C5 left side output shafts - that I hope to get modified to fit inside the diff. The outer end would mate perfectly to the half shafts.
126953de3bf176a59.jpg
The long one is long enough to cut off the end not needed and re-spline to match the C3 Diff. Will need to add a bit larger bearing surface to match the outer bearings in the diff - or get new bearings - for a just rebuilt diff! ARGHH. And, my machinist said, "...Oh splines. Uh, one of the machines I don't have." CRAP!

On the plus side, the wheels, wishbones, shocks and toe control are all coming together: :yahoo::yahoo::yahoo:
126953eb6f76418ac.jpg
The Lone bolt on the anti-roll is just for dry fitting. Need to do a bit of bending to get better alignment on the bar.

From the "inside":
126953eb6f76acf37.jpg

Here is a better look at the shock mounts:
126953eb6f774917e.jpg
Originally was going to use pushrods and rocker, but was getting too complicated and had some interference with the wishbones - so opted for this other approach. Involved some grinding and decreased overall weight and complexity for a slight penalty in partial unsprung weight.

Not related - but working interior too:
126953eb6f77ca7c2.jpg
The outer rails are for the underbody, side skirts and side pipe mounts. Should be building underbody bits this week and soon the firewall. Materials arrive for interior and dash soon - I hope.

And here she is - back on the floor:
126953eb6f777836b.jpg

That is the Plug I'm working on to build the flare molds. Looking at it - she is kinda nasty looking with that as a "skirt." I'm keeping that (aero) option open at this point.

BTW - the wishbones and toe control need to be re-accomplished -- the C5 half shafts will push the suspension/track out an additional 3 inches each side. Looks like the track will be 66 inches rotor-to rotor - or over 70 to outside of wheel/tire.

For "scale" the bottom of the fuel cell (not its cage) will be 7 inches AGL, which meets the GCR of 6" minimum. Ride height is settling around 3 inches +/- Makes getting a jack under a 4 step process. I may build a set of "horns/tangs" like a on a fork lift to slide inside the frame.
Fun fact - I raised the diff 2 inches. so the whole rear is lowered.

Well, back to the garage. If not to work, then just go and look at it...

Cheers - Jim
 
This is going to be an unsane build :nuts:

Yeah -- I'm just "wired" that way...

[apologies to script from Who Framed Roger Rabbit. Jessica Rabbit: I'm not bad. I'm just drawn that way. ]​

It really is starting to be fun - seeing some progress - BUT a long way from where your body work is Denis. I hope I can get it fired this season. Certainly won't get to TECH Inspection.

Thanks Pappy!

Cheers - Jim
 
His is inspiring -- but like mine has been moving slowly towards completion... These things take time I guess.
Hope to do some body work this next week or so... it should be equally "insane"

Cheers - Jim
 
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