While I was pondering over which LCAs and panhard bars to buy, I got the idea to buy all adjustable (on both sides) rod ends. So if I don't like them I can exchange the ends with rubber, poly or roto ones.

Problem is, I realized that the LCA bolt holes aren't the same with all cars. So this end for example: http://www.ridetech.com/store/rod-en...ng-insert.html
wouldn't work out because it's 5/8" id instead of 12mm or 1/2". Am I right?

Are there any poly and / or rubber "rod" ends for adjustable lower control arms with the correct hole for the 12mm bolt? I see that almost all aftermarket products have the 1/2" instead of 12mm (Founders is an exception).

Thanks,
Thomas

 

Yes Thomas you are correct. THe bushing insert needs to be the same diameter as the bolt that goes through it. The bushing also nees to be the same width as the chassis mount tabs and/or the suspension mount tabs it's going into or else you will have 1) a part that will not fit into the mount, or 2( a part that will slop about. The square peg goes into the square hole, etc

 

Hm, that's a pity. I can't find any ends with the correct measurements.

But as I've seen, the correct bore size would be 12mm. But all manufacturers except Founders Performance use 1/2" bores which is a wee bit bigger than 12mm. So the bore size shouldn't be such a big concern if the difference isn't too big.

What I thought was to buy rod/rod LCAs and then buy a UMI poly-end. Can't I just take out the poly bushing and replace it with a rubber one? Or are the moogs also another size? All I've found out is that BMRSuspension is the only other source for rubber bushings apart from Moog.

 

Just dril out the bolt holes in the chassis and axle slightly large with a 1/2" drll bit and then buy some grade8 1/2" bolts. It's really that simple. You just need to make sure the shank size is adequate for what ever arms you are using. Companies like ColemanRacing sell Aluminum Hex trailing arms which you can buy in any length. Once you get the ends you want to use that will fit, measure the gap between the ends and leave 1/2" thread exposed on each end. (ie- you need an arm 1" shorter than the max end shank thread depth). If you do not understand this then you are far bettter just buying stock replacement arms OR buying aftermarket ones with dual JohnnyJoints like Spohn and Umi sell (ie- Delsphere joints of Rotojoints- both pretty much the same copies of Johnnyjoint type ends orginally designed by Currie)

 

I was going to post a thread with this question but it fits here. What are the relative merits of a regular spherical rod end and the Delsphere joints? What do the DS joints give for the extra money?

 

The largest thing to make sure of is what style of rod end a company is using, there are several different "levels" of rod ends. Make sure to keep this in mind if you go that route. The delsphere/roto/johnny joints all are of a rebuild-able style, which is great, but I have never seen the need for them in our cars. They are great for off road applications where you are wanting the increased articulation that is allowed with a rod end, the relative quietness of a poly/rubber joint.

If this is a driver and not a racer I would go poly/poly.

 

And what are your arguments against rubber/rubber or poly/rubber for a daily driver?

 

For a daily driver I don't see the point of using anything other than the stock rubber bushes. Especially for some of the rear where it seems the poly would just bind even more than the rubber. Save the money for something else.

 

The only thing I could think of as an advantage is a little bit of better handling and longevity. How long is rubber supposed to keep its function? I guess all vehicle come with rubber bushings stock, even today? Or is this only with our F-bodies and their rear?

 

Almost every vehicle comes with rubber stock. It does its job perfectly, lasts a very long time in all sorts of conditions and is relatively cheap. Very few people can/will reach the limits of what the vehicles with rubber bushes can do. Depends on how much you want anything else, what you really want to do with the car and how much you want to spend.

 

Not really an argument against, but, personally if I change I would want the improved performance of poly. That and trying to find an adjustable LCA with rubber ends would be difficult.

 

Well BMR offered me their adjustable LCAs with rubber bushings on both sides. Later on you can easily change to poly bushings. But for me, I don't think I'll ever need adjustable LCAs. Even if I lower the car an adjustable panhard bar should be enough.

 

Id rather have rubber bushings than poly/poly. You want that axle to articulate.

 

I was seriously just about to ask this. I heard some noise and had a weird squirming feeling from the rear of my car... turned out to be the PHB. The bolts are slightly loose in the holes. I am surprised that I haven't heard more on the issue until now and that the manufacturers sell rod ends on their PHB's and LCA's without supplying hardware or instructions on modifying the chassis holes.

Seems this guy ran into the same thing:
http://ls1tech.com/forums/suspension...l#post16818753

The factory inner diameters of the bushings are also larger than the hardware, but I suppose that there's less movement with the rubber bushings crammed in and torqued down... also less noise. Going to have to try this, I hate seeing my shiny aftermarket PHB sitting in the corner of my room.

 

Guys the difference in 1/2" vs 12mm is no issue at all. There is no need for a precision fit. When the bolt is torqued all it is doing is clamping the joint. The friction from the clamp is what is holding the parts together. In fact you could remove the bolt and install a c-clamp instead at the same torque, and the same function would be maintained.

This idea that the parts are loose on the bolt is common but false. If you are getting noise from the joint hitting the bolt, then your bolt is not torqued to spec.

Regarding the delrin lined joints like the del-sphere. The beauty of these joints is they are smooth articulating, quiet, and maintenance free. You have your cake and can eat it too. A quality rod end that will provide a long quiet life will be double the price.

I will not use poly bushings on articulating parts as they are not smooth articulating and are not quiet. I would MUCH rather use stock rubber.

 

GW website text:
The bushings in the lower control arms are basically the problem. If you look at the lower control arm bushing you will notice air gaps on each side of the center bolt hole. The air gaps allow the differential to move fore and aft and also shift during cornering. The panhard rod has nothing to do with this movement. So what happens as you accelerate out of the corner, the rear end actually shifts and points out of the turn. This helps the car oversteer. Something we don�t really want.

For straight line acceleration the rubber bushings can generate an oscillation leading to reduced traction. Aftermarket polyurethane control arms solve some of the problem and create others. The polyurethane does not allow the differential to pitch as it needs to around corners and over bumps. The result is again oversteer and a stiffer ride over bumps. Straight line acceleration is better because we have removed the air gaps in the rubber.

Replacement rubber bushings are available without the holes and again an improvement over the stock setup is achieved. However there still is a problem. The rubber increases resistance as the suspension moves through its intended path. Thus changing the spring rate and we still have some deflection through the control arm and bushing. Some people box the lower trailing arm to gain handling, however boxing the control arm increase the resistance during corning and again effects the rate the car sees. This leads to oversteer.

The solution is Global West Suspension�s Quite Ride TBC-14 rear lower control arm. The arm is designed with a spherical bearing on one end and a rubber bushing on the other end. There are no holes in the rubber bushing. We deliberately designed the arm to use rubber because the bushing acts as a noise insulator for the street but yet we still have the control for high performance driving including racing because the bearing and the tubular arm don�t deflect.

From their site, it looks like you can order solid rubber bushing replacements!
I like the Del-Sphere for axle side - just ordered three with LCARB's.