Crazy Driveshaft Idea: CV Joints

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Longitudinal
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Crazy Driveshaft Idea: CV Joints

Post by Longitudinal »

Yeah, I suppose it sounds pretty loony, but let me say why: I have heard some stories of slight vibrations with T5 conversions due to the need for pinion angle adjustment. CV joints don't care about angles.

I have stacks of Audi CV shafts from which I could harvest telescoping or non-telescoping joints. If I do a T5 or C4 conversion, I would want a pair of non-telescoping joints.

I would then cut off a section of axle bar for each end, then machine each stump of axle to accept a machined piece that would step up to a suitable size tube for a driveshaft. Weld weld weld and I have a driveshaft.

From there, I would need to make a slip yoke adapter and an adapter to the Merkur differential flange.

Yes, I could just buy a Fox driveshaft and an adapter, but I think the cost my way would be comparable or even less.

Crazy?
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Esteban
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Re: Crazy Driveshaft Idea: CV Joints

Post by Esteban »

If you've got the time, try it out. Might be easier to convert a 2 piece DS by deleting the guibo and adding a T5 yoke and u-joint. Shouldn't get any vibes compared to a 1pc.
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Re: Crazy Driveshaft Idea: CV Joints

Post by my8950 »

You have a plan and the stuff to make it, I'd say go for it. I'll be needing a D/S soon for a manual swap...
Longitudinal
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Re: Crazy Driveshaft Idea: CV Joints

Post by Longitudinal »

Esteban wrote: Tue Feb 06, 2018 8:04 am If you've got the time, try it out. Might be easier to convert a 2 piece DS by deleting the guibo and adding a T5 yoke and u-joint. Shouldn't get any vibes compared to a 1pc.
But converting as you have described still puts U joints at both ends. I'm not concerned about whether the shaft is one piece or two piece. I am more concerned and setting up a vibration between two U joints that do not have proper angles. I think the reason for the guibo in the first place was to soak up vibrations so that the car's occupants didn't feel driveshaft vibrations.

If plenty of people have one piece Fox driveshafts in their cars with zero increase in NVH, then I will not try to reinvent the wheel.
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Re: Crazy Driveshaft Idea: CV Joints

Post by thesameguy »

I think you can't just be sloppy with the install. If you get it aligned properly, it should be fine. Don't get me wrong, a one-piece driveshaft will be more prone to vibration than a two-piece with rubber in the middle, but done right could just be the difference between a Ford and a BMW, if you know what I mean. Not ideal, but fine. I used aluminum to reduce weight and thus vibration, and I've been happy. It could be better I'm sure, but I saved a fair amount of weight and eliminated a weak spot (rubber...) so the tradeoffs were worth it. Price-wise, the aluminum driveshaft and 460 adapter was cheaper than I could have had anyone around here weld & balance something custom. OTS wherever I can...
Longitudinal
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Re: Crazy Driveshaft Idea: CV Joints

Post by Longitudinal »

In my neck of the woods, I can get a custom driveshaft for about $300. And I have a Pinto shaft to start from, so if I could start from the XR4 diff flange and eliminate the adapter there, I could get away cheap.
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Re: Crazy Driveshaft Idea: CV Joints

Post by markley007 »

I had a SN95 v6 Solid drive line with no vibration (even when i took her up to 135). I think if done right with a good balance and good bushings and seals for the tail shaft and transmission mount , you should not have a vibration. If you do , you should check your alignment with the trans to the rear end .
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Re: Crazy Driveshaft Idea: CV Joints

Post by merk23literturbo »

Your not talking about the real problem, the angles have to be the same on both ends and 3 degrees is what's normally looked for. You can read my other post about it, I've been playing with the problem for a long time.
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Re: Crazy Driveshaft Idea: CV Joints

Post by mopman93 »

Modded two piece ftw. And make sure you don’t have the tail housing too low.
I’ve got one, my buddy’s got one, my other buddy’s got one... you can get a front shaft modded for $150 around here with new joints and yoke.

Cossie’s ran a similar two piece drive shaft two an xr with a t5. Although I believe the rear section of that ds was a two piece with rubber in between the inner and outer walls.
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Scott779
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Re: Crazy Driveshaft Idea: CV Joints

Post by Scott779 »

The bronco 2 rear drive shaft had cv joints, when mine was rebuilt, the guy told me it was basically a tempo 1/2 shaft with flanges instead of splines
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Re: Crazy Driveshaft Idea: CV Joints

Post by twin turbo »

I have one piece shaft in one of my escort Cosworth with 2wd, no vibrstion there either...
Last edited by twin turbo on Thu Feb 28, 2019 6:22 pm, edited 1 time in total.
my8950
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Re: Crazy Driveshaft Idea: CV Joints

Post by my8950 »

Rather than the rubber guibo, haven't some people had a universal joint installed? Sorry if I missed this above somewhere already.
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