Looking for RT-4 CV’s

[RoWatso]

Hello Forum Members:
I’m hoping that someone can help me with finding/sourcing a set of four CV joints that will fit a 1986 Ralt RT-4. I’m starting a total restoration of the car and the old ones will need to be replaced. And if anyone knows or has any spare RT-4 suspension bits or other parts available for sale please let me know.
thank you in advance for any assistance you can provide.
Cheers,
Rob W.

[Charles Warner]

Hello Forum Members:
I’m hoping that someone can help me with finding/sourcing a set of four CV joints that will fit a 1986 Ralt RT-4. I’m starting a total restoration of the car and the old ones will need to be replaced. And if anyone knows or has any spare RT-4 suspension bits or other parts available for sale please let me know.
thank you in advance for any assistance you can provide.
Cheers,
Rob W.

Rob,

Check which style halfshafts you have. If they are original they may be the old 23 spline axles. If so, those straight plunge CV joints are unobtainable. (I think they were originally early Audi FWD joints.) Your only option is to have two new axles made in the later VW/Porsche 33 spline design (which is pretty much standard now) and source new lightened CVs from Scotty. You can get the axles made at any southern California off-road prep shop. Send them what you are replacing and they'll made what you need. They'll be heavy. (Of course, you can pay to have then gun-drilled. I wouldn't bother). If you have the 33 spline axles, just source the new CVs from Scotty.

[billtebbutt]

Rob,

Check which style halfshafts you have. If they are original they may be the old 23 spline axles. If so, those straight plunge CV joints are unobtainable. (I think they were originally early Audi FWD joints.) Your only option is to have two new axles made in the later VW/Porsche 33 spline design (which is pretty much standard now) and source new lightened CVs from Scotty. You can get the axles made at any southern California off-road prep shop. Send them what you are replacing and they'll made what you need. They'll be heavy. (Of course, you can pay to have then gun-drilled. I wouldn't bother). If you have the 33 spline axles, just source the new CVs from Scotty.

Charles were those CVs you are referring to also used on the March Atlantic cars? My 78B had them, and I had to go the new axle/CV route you suggested. I had *heard* that they were off a Leyland truck of some sort, but that was about 1000 years ago.....

best
bt

[Charles Warner]

Charles were those CVs you are referring to also used on the March Atlantic cars? My 78B had them, and I had to go the new axle/CV route you suggested. I had *heard* that they were off a Leyland truck of some sort, but that was about 1000 years ago.....

best
bt

They were used on most of the larger formula cars of the era. Easily could have been from Leyland.

[RoWatso]

Rob,

Check which style halfshafts you have. If they are original they may be the old 23 spline axles. If so, those straight plunge CV joints are unobtainable. (I think they were originally early Audi FWD joints.) Your only option is to have two new axles made in the later VW/Porsche 33 spline design (which is pretty much standard now) and source new lightened CVs from Scotty. You can get the axles made at any southern California off-road prep shop. Send them what you are replacing and they'll made what you need. They'll be heavy. (Of course, you can pay to have then gun-drilled. I wouldn't bother). If you have the 33 spline axles, just source the new CVs from Scotty.

Charlie:
I just checked my existing half-shafts, they are (of course) the old 23-spline. Therefore it appears that I will be moving into the current century with 33-spline half-shafts and newer style CV’s. I appreciate your input on sourcing through Scotty for the CV’s, and the lead on possible sources for half-shaft fabrication.
Thanks again,
Rob

[SteveG]

You can also try FastForward for your half-shaft needs
https://www.fastforwardracingcomponents.com/
Besides race car stuff, they have a full cnc machine shop.
The Dougs (Sr and Jr) are very good people.

Steve

[scorp997]

I believe there are some other cars that use a 23 spline CV. One that comes to mind is a Mitsubishi Lancer EVO inner joint. It looks like a straight plunge style, but is wider than the typical CVs I’ve used. Not positive of the bolt pattern either, but there may be other options out there before swapping axles

[RoWatso]

You can also try FastForward for your half-shaft needs
https://www.fastforwardracingcomponents.com/
Besides race car stuff, they have a full cnc machine shop.
The Dougs (Sr and Jr) are very good people.

Steve

Steve - Thank you for the information on Fast Forward.
Cheers,
Rob

[stonebridge20]

Charles were those CVs you are referring to also used on the March Atlantic cars? My 78B had them, and I had to go the new axle/CV route you suggested. I had *heard* that they were off a Leyland truck of some sort, but that was about 1000 years ago.....

best
bt

Those were called Pot joints and they were from a Renault truck.

[Phil Creighton]

I know that Howden Ganley at Tiga fronted up for a large batch of these with Ralt and March when they became hard to get back in the day. Pretty sure they were made by Hewland at the time. He and Ron Tauranac did a few deals like this I recall.
Doesn't help much in the current situation Just a bit of history.............
Phil

[RoWatso]

Phil - Thanks for the “history” information. It’s always good to understand what transpired in the past to get us where we currently are. Thanks for chiming in.
Cheers,
Rob

[Raleigh]

For those RT4 owners running the 33 spline Drive shafts and CV's the Part number required is 7 153 10 01 98 003. They are made in Germany by Lobro, sourced from an Audi / VAG group vehicle.

I have another type with the part number 19-VW15 which I believe is made by Oetiker and identical to the Lobro items dimensions.

** Update: I have found some in newer GKN packaging. The part number for the Std weight CV is: GKN301116

The light weight version is: GKNMSJ003

[RoWatso]

Raleigh:
This is absolutely very helpful information. Thank you very much. I’m looking for some of these Lobros now. One more question for you (and others) to help everyone who needs some replacement CV’s for their RT-4 (or other) if you don’t mind. Do you recall where you got the halfshafts from, or the shop that fabricated them for you?
Best Regards,
Rob

[Raleigh]

Mine were made many years ago and likely in the USA. If I needed replacements in my Area of the world I would commission Motorsport solutions in New Zealand to make them.Also bear in mind that RT4’s have many different rear track widths, You May find a pair of 33 spline RT4 drive shafts but they may not work with the width / track of your chassis.

Raleigh:
This is absolutely very helpful information. Thank you very much. I’m looking for some of these Lobros now. One more question for you (and others) to help everyone who needs some replacement CV’s for their RT-4 (or other) if you don’t mind. Do you recall where you got the halfshafts from, or the shop that fabricated them for you?
Best Regards,
Rob

[Charles Warner]

https://www.chirco.com/dune-buggy-an...s-drive-axles/

[RoWatso]

Thank you Raleigh and Charlie for the additional information on halfshafts. It should help a few of us.

[Raleigh]

** Update: I have found some CV Joints in newer GKN packaging. The part number for the Std weight CV is: GKN301116

The light weight version is: GKNMSJ003