Steering rag joint

[stealthyflatfish]

Anybody taken the rag joint off the steering column and replaced with a universal joint, do you get more vibration through the steering wheel ?
Does it make it feel firmer ?
And anybody know the diameter of shaft and number of splines required ?
Thanks in advance.

 

[Oneball]

The sizes will be dependant on your car’s year.
I looked into this and all the race cars even the nuts Greenwood ones use a rag joint. I’m not sure why but it could be the flex is needed, I put a rag joint back on mine.

 

[stealthyflatfish]

Thanks for your reply Oneball, was just toying with the idea whilst looking through a catalogue, lockdown has got me wanting to tinker with something just for the record it's a 71.

 

[Oneball]

Bit more discussion here

alternatives to rag joint - CorvetteForum - Chevrolet Corvette Forum Discussion

C3 Tech/Performance - alternatives to rag joint - Hey guys, as the title says, are there any alternatives to the factory rag joint between the steering column and the box?

www.corvetteforum.com

 

[stealthyflatfish]

Blimy, have you seen how much Flaming river charge for theirs
Flaming hell !

 

[Rich]

Bit more discussion here

There's a very informative explanation which I have repeated below:

"Back 43 years ago, I was a product engineering design group supervisor. I was responsible for flexible steering shaft couplings and power steering pressure hoses for the C2/C3 Corvette and all the other GM vehicles in the 70s and early 80s. So I do have quite a bit of experience with these products.

In those days, virtually 100% of the General Motors passenger cars had a rigid frame and a seperate body mounted to that frame with rubber body mounts. Those General Motors vehicles also utilized a rubber element between the steering column (part of the body) to the steering gear (part of the rigid frame.) There were four basic reasons why there was a flexible disc (with 4 or 7 laminations of neoprene rubber and cotton cloth) in the shape of a flexible steering shaft coupling assembly. The functions of that part were as follows:
1). Absorb rough road shocks from reaching the steering wheel.
2). Isolate road and hydraulic noise from being transmitted into the driver compartment.
3). Allow for body to frame tolerance and minor movement between the body and frame as the vehicle is being driven.
4). Accommodate any design angle between the steering column and the steering gear.
5). Provide a reliable ground path for the horn.
I think that there are universal joints that have a rubber damper element as part of the design. This would allow the part to accomplish the function of #1 , #2, and #4 above. I'm not sure about #5.

However, a universal joint is very rigid therefore it wll not allow for any misalignment of the steering column to the steering gear. Also a universal joint will not allow for body to frame movement.

Our fear, as the design responsible steering Division, was that the lower column bearing and the lower steering column jacket would not be able to absorb any movement of the body to the frame during the life of a car. Therefore a rubber element between the two was required.

Now I am fully aware that there are many aftermarket steering systems for the C2/C3 Corvettes that now incorporate a universal joint. Also I am fully aware that quality flexible coupling assemblies are becoming quite rare.

So the best that I can do is try to council people making installations with rigid univeral joints is to keep a close eye on the installation and be alert to any looseness or degradation of the lower steering column bearing."

 

[Alben78]

Changed the rag joint on the 78 some time ago. First try was with one of the repair kits but when it arrived it looked decidedly suspect in terms of the Flexi bit and the fittings so it was disposed of. A genuine GM replacement sourced from the States was quite expensive but looked much better. I found it easier to remove the steering gear rather than mess with the column and also cleaned up the gear at the same time. Must say it seemed to improve the feel and eliminated some of the vague slop that the original one had developed over nearly 40 years. Not that it was driven much by that stage.

 

[Vetman]

In my recent note on 40 years of C3 ownership, I mentioned the state of my rag joint when I first owned the car. All owners should look at theirs and check for any lost motion. Any improvement worth having.

I fitted the Steeroids system to mine several years ago and this has two universal joints close together. This mechanism probably provides some flexibility as the rag joint did.

Photo attached.

 

[stealthyflatfish]

Well that's that sorted then, stick with a new quality rag joint, if you can find one, thanks for your input gentleman.

 

[antijam]

The advantage of the rag joint over a U/J set up is that while its torsional stiffness is high, the axial and radial stiffness is low and the rubber is an excellent medium for isolating vibration. Replacing the rag was one of the first jobs I did on my '71 (see here) - the steering when I bought it was pretty wayward and the replacement, plus adjusting the slack out of the box, has made a great improvement. CK do a good quality replacement joint for around £50. Incidentally I removed the steering column to do the job - hindsight suggests swinging the box out of the way is probably easier.