View Full Version : Johnny joints
no go nova
07-06-2013, 07:08 AM
Has anyone you johnny joints in place of heim joints for front upper and lower control arms?
http://www.currieenterprises.com/cestore/johnnyjoints.aspx
Typhoon1015
07-06-2013, 07:46 AM
I have not seen these used in car applications. Currie makes curritrac's for chevelle's I know.
UMI has a nice set of rotojoints if your looking for a rebuildiable joint. I have a set of those and am really happy with them.
no go nova
07-06-2013, 08:15 AM
I wil check them out thanks
astroracer
07-06-2013, 10:13 AM
I used them in the upper and lower bars in the van. Of course I haven't gotten it on the road yet so no review... I can tell you they are stout and I see no issue with these things breaking ar wearing out like regular rod ends do...
Mark
Ziegelsteinfaust
07-07-2013, 08:42 AM
I always believed Johny joints were for link suspension especially one 4wd's where you want to get a bit more articulation out of the set-up. Also I have seen guys use them on 2-link trucks to get a touch of articulation when going up driveways thus making it noticeably easier from what I under stand.
Would it it articulate in a front end to much causing handling issues? Unless your running early Ford suspension like on a Mustang where it would be awesome for the track bar for the lower A-arm.
no go nova
07-07-2013, 09:40 AM
you can adjust the preload so it can't articulate to much with shims.??
UMI Performance
07-07-2013, 10:36 AM
We build a few different widths for the Roto-Joint, most of our widths are GM sizes so they work with virtually any GM application. You would need to PM us though to get the right width since they aren't all listed on our site.
The Roto-Joint is rebuildable and adjustable, you can tighten them to need more force to move them, yes.
http://umiperformance.com/catalog/index.php?main_page=roto_joint
Please let me know if you have any questions. thanks!
Ryan
carbuff
07-07-2013, 05:50 PM
Ryan,
I have a couple of questions about these types of joints. Hopefully you can excuse my ignorance. :)
When I was assembling my rear suspension, I was wondering if a joint like this would offer some type of advantage over a heim end or regular poly bushing setup. I have a torque arm in my 2nd gen with 2 lower control arms in place of the original leaf springs to locate the axle. One of the problems I faced was that the width of the poly bushings I use causes the LCA to be closer to the wheel/tire than I would like, so if I could find a joint like this, I could possibly move the LCA inward.
But then I started wondering about the articulation of the joints through rotation of the rear axle. It seems that a regular poly bushing would bind during the arcing rotation. My setup has a Watt's Link, so there should be minimal side to side movement, but if the LCA isn't perfectly straight, then I would expect some binding.
I would think in that case that these types of joints would be a good replacement. Is my understanding correct?
Usually things like these come with compromises though. ;) So, what is the downside to using a joint like this instead of a poly bushing?
Finally, you mention different widths. What is the minimal width to which these can be made? As in my case, part of the desire would be to move my link inboard. Currently I have bushings that are around 2.5", maybe 2.625", in width. How much narrower can these joints be?
I appreciate the education. :)
astroracer
07-08-2013, 03:45 AM
I have to apologize to the OP after actually "reading" his initial post. Using the JJ's in the FRONT suspension is not going to make a difference. You COULD use them, at a greater expense then a heim joint or solid poly bushing but, the front control arm bushings don't see the same "articulation" (front to back) that the rear suspension sees side to side. The inner pivots on the front control arms are in-line and usually held that way with the bushing shaft so the arms can't pivot any way other then about the shaft centerline. Some arms do run heim joints, which have a similar rotational function as the JJ's, but this has nothing to do with overall arm movement. The heims simply remove the "flex" of a poly or rubber attachment. Hope I was clear..
Mark
BallisticFab
07-08-2013, 02:44 PM
Hey guys, we thought we'd chime in here. We make a cartridge style joint called the Ballistic Joint that's similar to the Johnny Joint. We've got some customers using Ballistic Joints on their street cars and pro-touring cars and they seem happy with them. We were of the impression that our joint, and joints like ours, would be too "squishy" for track use or aggressive street use because of the poly races, but our customers are happy with them. The main benefit, at least that we can think of, is that a cartridge style joint will eliminate some of the NVH that is characteristic of a heim joint. The heim joint is going to deliver the most solid feel but it will transmit vibrations through the suspension arms and into the car. The JJ is a great product, a lot of people use them and really like them. The main complaint that we hear is the non-adjustability of the joint. Once the race starts to wear the joint will get sloppy. We use a spanner nut so that if the race starts to wear you can tighten the spanner and keep the joint nice and stiff.
As far as performance, a heim has no play but will eventually wear out. Once they wear out they cannot be rebuilt, they must be replaced. Cartridge style joint, like the Johnny Joint can be rebuilt relatively easily.
We hope this helps!
Bryce
07-08-2013, 03:36 PM
Thanks for chimming in!
Kenova
07-08-2013, 05:18 PM
.... The inner pivots on the front control arms are in-line and usually held that way with the bushing shaft so the arms can't pivot any way other then about the shaft centerline.......
Mark
There is one exception. Some control arms (usually lowers) use cams to set front end alignment. These can offset the centre lines of the bushings/joints. It is a very small offset and usually doesn't cause any binding unless you are using a hard bushing like delrin or even steel.
Seems to me that there are ball style control arm joints available for Corvettes for this very reason.
Ken
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