Spherical bearings

[Dat260]

Hey guys,

Would this upgrade be overkill for a street driven Zcar? I downloaded the pictures from JohnC's gallery.

Thanks,

[blueovalz]

In my mind it's hard to reach that point of overkill, but (depending on if your application is for the street) for me, I like the control arm bearing, but would skip the T/C rod bearing (unless I put the car on the track).

[JMortensen]

There are easier ways to get a heims joint into the suspension. That is rc240z's car I think. He has a BRE replica. If you're not building a replica search for "custom lca" or "rod end lca" and you'll find lots of threads on chopping the control arm in half then putting a rod end on the end of it. The advantage there is that you can change the length of the rod end (and the TC rod when you do it that way too). I drove my car on the street for years with camber plates and rod ends on the control arms and TC rods. Wasn't a problem for me.

[katman]

That T/C spherical scares me. Coupla tack welds holding it in? Wrong load direction for a spherical IMHO.

 

Now I've had spherical everything on my race cars but a good poly bushing is all I use on my street/dual purpose cars. Maybe I'm getting old...er.

[mom'sZ]

Hey Katman:

 

While we're on the subject of spherical bearings for Zcar suspensions, I've got a question (or two). You replied to an earlier thread about spherical bearings, here is a link

http://forums.hybridz.org/showthread.php?t=102277&highlight=spherical

 

in that thread you state:

"Don Oldenburg at DP Racing in Huntington Beach still makes the Mac Tilton/BRE front control arm speherical bearing setup for a Z. Don's retainer is tack welded to the arm"

Is this the right DP Racing http://www.designproductsracing.com/DesktopDefault.aspx?tabid=514

Are those the right front control arm bushing kits to which you refer? Do they indeed tack weld in and is that IT legal?

 

Then in a thread titled '240z steering issues' on improvedtouring.com forum on April 6 2005 you state:

What you have is the old Kontrolle style T/C rod kit that's been around since 240Z's were new. The poly squishes out on a regular basis, especially on driver's side depending on how close the headers come, and on how much you preload them. The Crawford Monoball is a spherical bearing setup made by Crawford Z Car Services in Tenn. Call Doug Stewart at 615-327-4159

 

Is this the Crawford Z car service to which you refer?

http://www.crawfordzcar.com/

I don't see anything for older Zcars on the site, do you know if they still have the monoball set up for the T/C rod? My car is a 1978 280 BTW

And how do the ones Motorsport Auto sells stack up, are they the same thing? Here's a link to them

http://www.zcarparts.com/store/merchant.mvc?Screen=CTGY&Category_Code=PSDC10

 

What other goodies are available? What suggestions do you have for spherical bearings for the Zcar?

[Here comes trouble]

Stock Car Products sell the FK brand com 10 (5/8 inch insided diameter) monoball bearing for less than $8.00 and most of these monoball bearings offered for sale by vendorsw are made by Aurora in Indiana USA. One of the links posted is selling a com 10 bearing for $25.00 with no vaseline. http://www.stockcarproducts.com/rodend6.htm

[katman]

Hey Katman:

 

Is this the right DP Racing http://www.designproductsracing.com/DesktopDefault.aspx?tabid=514

Are those the right front control arm bushing kits to which you refer? Do they indeed tack weld in and is that IT legal?

 

 

Is this the Crawford Z car service to which you refer?

http://www.crawfordzcar.com/

I don't see anything for older Zcars on the site' date=' do you know if they still have the monoball set up for the T/C rod? My car is a 1978 280 BTW

And how do the ones Motorsport Auto sells stack up, are they the same thing? Here's a link to them

http://www.zcarparts.com/store/merchant.mvc?Screen=CTGY&Category_Code=PSDC10

 

What other goodies are available? What suggestions do you have for spherical bearings for the Zcar?

 

All those sites are correct. The MSA T/C kit is what I was referring to with my comment about the plastic degrading over time. Call Crawford, ask for Doug, then ask if he can still make the spherical T/C bearing for ITS 240Z's. Bet he can. The DP racing control arm kit can be IT legal if you epoxy or press fit the pieces that capture the bearing. No real fore/aft loads so not a lot of strength needed. A "rules nerd" may have a problem with a tack weld in ITS but I'd do it anyway for convenience and take my chances in Tech.

 

Other spherical bearing apps for ITS? Well the upper camber plates usually have one to locate the top of the strut of course, but otherwise no. Since you can't hack up the rear control arm in ITS you don't have the room on either end for a spherical bearing, so a sleeve bearing is required. We used Nylatron for the outer bearings, and the inner bearings were offset like the old Kontrolle camber/toe adjust kit commonaly available from places like MSA, except I made my own using Oilite Bronze sleeves and nylon thrust surfaces and a design not as prone to binding as the originals.

[mom'sZ]

Thanks katman, I knew by the letter of the rule tacking the bushing to the control arm might be considered modifying it. But bushings are free so to me so would be their method of attachment. Sounds like another gray area so typical in IT rules. Will call Crawford about the T/C rod ones.

[Dat260]

Thank you for the replies, guys.

Ari.

[peej410]

as far as spherical bearings are concerned in the TC rod pickup point, i will be doing this, but my own way... ive yet to draw it up because i havent had the time but the research ive done has said that the maximum axial load (through the hole) of a spherical bearing should be 15% of the static radial load capacity (pulling against the bearing) meaning that a good 3/4 spherical bearing (mcmaster part# 63215K39) rated at about 46,400 lbs static radial load, would be good for 4,640 lbs of axial force. the heim rods most people use are barely rated for 8,000 static radial load. moving up to a 7/8s spherical bearing bumps you upto 62,200 static radial, and 6,220 axial (mcmaster part# 63215K41) i dont see where the strength issue is with a spherical bearing in the TC rod pickup point.

[tube80z]

Why don't you use something like rack ends. Sentra ones work well.

 

Cary

[peej410]

Why don't you use something like rack ends. Sentra ones work well.

 

Cary

was this directed towards me?

[tube80z]

was this directed towards me?

 

No, just a general comment on a possibly easier way to do this. Unless there's a specific reason you need to mount a spherical. The rack ends offer an easy solution to making an adjustable TC rod and having a strong joint that you can boot.

 

Cary

[Jolane]

Tube80z,

Do you have information on the strength of a rack end? I cannot image a rating for these things since it seems like most of the loading is rather low compared to a TC rod. I was thinking along he lines of using a GM draglink from the front axles of a truck. This would require some changes to the TC mount. I could imagine bolting the rod end through the frame rails (this is hard to explain, so I will stop there).

In the end, my car is for the street, so I just want a robust TC rod and minimal road vibration. I am thinking of a custom TC rod but then use the poly front and stock rubber rear bushings in the stock cups. By making a TC rod I would like to increase the diameter of the stud going through the bushings (modify the bushings ID).

Joshua

[tube80z]

Tube80z' date='

Do you have information on the strength of a rack end? I cannot image a rating for these things since it seems like most of the loading is rather low compared to a TC rod.[/quote']

 

I don't know the loading they can handle. The idea has been around for a long time and described in the original 510/Z Hot Rod book, which used British parts. I can tell you that I've never seen an inner pivot come apart even though I've manged to turn the steering arm into spaghetti. And on the Z the loading is in compression for the most part on the TC rod.

 

Cary

[mom'sZ]

there ia another current thread in which using a rack end for the T/C bushing is disscussed. I think you'll find it interesting as using the rack end alters the front end geometry unless you relocate the mount. Here's a link

 

http://forums.hybridz.org/showthread.php?t=106522

[Jolane]

Cary,

I do realize that the loads are largely compression given that the car is rear wheel drive, and braking and accel loads are all compressive on the TC. Backing up is the only major loading conditions I can think of, and how much can that really be considering the speeds. I would assume that cornering also exhibits loads on the T/C rod, but can't quantify that reasonably. Most of the cornering load goes into the LCA.

The loading of a rack end seems to come primarily from tire scrub or bumps. I have seens cars hit curbs and totally mangle the A-arms, spindles, etc, but the rack end still holds together.

I wish there was a clean way to rubber mount the T/C rod. I realize that this defeats the purpose of using the rod end (stability, lack of excess deflection, etc). I have also been thinking along the lines of using a standard poly bushing in a configuration similar to a track bar (panhard rod). The back of may cars have these as well to control the fore/aft wheel motion, like a drag link. This would require modifying the T/C cup, but I would think the gain is worth it. It could create more room for headers, starter, etc while limiting transmitted vibration. It wouldn't be too hard to implement either if your already working on that area anyways (which I am).

I just really want a street method that doesn't have me breaking T/C rods later. Something robust, more accurate handling, vibration "free", etc.

Joshua

[tube80z]

I do realize that the loads are largely compression given that the car is rear wheel drive, and braking and accel loads are all compressive on the TC. Backing up is the only major loading conditions I can think of, and how much can that really be considering the speeds.

 

This was also done on 510s and then the TC rod is in tension. No issues with the same pieces here.

 

I wish there was a clean way to rubber mount the T/C rod. I realize that this defeats the purpose of using the rod end (stability, lack of excess deflection, etc). I have also been thinking along the lines of using a standard poly bushing in a configuration similar to a track bar (panhard rod).

 

Basically boxing in the TC rod and having a bolt across that the busing pivots on? The only thing I'd see being an issue would be the the axis everything moves about will twist your bushing. In the back end of a 510 this generally leads to squeaks.

 

Cary

[Here comes trouble]

I have both FK and Aurora monoball com 10 (5/8") bearings and upon initial inspection can find little difference in the tolerance of bearing and race of monoball..... both have a hole for grease by the introduction of a zert in the seperate housing or cartridge for the monoball bearing

[Jolane]

Thanks for the info Cary. Used in tension, now that is starting to sound nice and strong.

You have that right about the twisting seen by a bushing. That is the downside. I am not really sure how much twisting a standard bushing can take, and maybe that is a bigger problem. What if is can't take a lot, then the TC rod gets twisted, which can be bad.

I will most likely just use beefed up TC rod for my project with a poly compressed bushing and a stock rubber tension bushing. Eventually I want to build another 240 (my '70), and at that point I think I might do a true A-arm on it. The plan for that car includes cutting the front end off at the firewall also, and building a full tube frame front end. I think this would make it easier to use an A-arm front end. Even with my beefed up frame rails, I am not sure I would trust an A-arm for my current project.

Wouldn't an A-arm be the best here. It could be easily tilted for better anti-dive, allow wider tires and/or sharper turning radius, robust, etc? Seems like this would be ideal, nd could potientally save space as well. Just need some stout frame rails. Maybe just go Mustang II front end, no more strut towers, even more space.

Thanks for the discussion,

Joshua