Hello,
Well I'm close to purchasing a whole heap of new suspension goodies for the teg, and I have some questions for you suspension gurus. First let me say that my car is mostly just used for racing. I don't drive it on the roads except for the ocasional Sunday drive threw town. I haven't driven it for the past 10 months, and I don't plan to drive on the roads around PA too often when its up and running again.

Im interested in getting the SRR lower control arms for the rear, and the caster/camber adjusters for the rear and also the toe in/out for the front and rear.
On the mounting points (the bushings), you have an option of going with the standard rubber, or for a small additional cost you can go with the metal spherical style end-links. My main question here is what are the advantages of the metal end-links? Are they streetable in my application? Has anyone heard any race rumors of these auroa style links bending or breaking? Thanks!~
For PICs go to this exospeed link for examples of what I am talking about...
http://www.exospeed.com/specials/srrnew.htm

 

I wouldn't be too concerned about bending or breakage on the street unless they go into a bind. A spherical bearing on the street will transmit a lot of road harmonics and frequencies right directly to the chassis that honestly the chassis has no need for so it will show up as harsher ride and faster wear and tear. I generally would say don't do it on a street car as there is no real need but since it is a racecar whtn it is certainly up to you. Comparing mileage and wear on sphericals to rubber, the rubber will last much longer over time but a racecar normally will only see a fraction of the mileage through the rest of it's life.

Normally sphericals do tend to allow more adjustment but sacrifice ride harshness bigtime and wear quicker but if it is not for the street then harshness is not really an issue. Don't expect any big performacne gain so they should be used on a pretty darned well developed car so the money spent on them wouldn't necessarily be better spent on something else on the car that would make a more noticable performance gain. Aggressive strut cars can pretty easily gain benefits from camber/caster plates with sphericals but these are not strut cars and sphericals in the control arms will give only slightly better gains than a properly rubber bushed control arm.

 

Thanks CRX Lee; that was an awesome answer. Hmm- I still am a bit confused on what I shall buy... Can you tell me what the performance differences are? Like- why a car would run sperical in the first place? The extra $ isn't that big of an issue to me, heres my rundown on importance: 75% performance factor, 20% part life, and 5% cosmetic- (haha!). From what you wrote, it sounds like everyone (strictly racers too) would choose the rubber over the bearing type- theres gotta be something that these metal ones have over the rubber!

 

Spherical bearings result in more positive motion. When working properly (not binding...which is easier than you'd think), a s-bearinged control arm sees a very small amount of joint friction. A rubber bushing provides a bit more, though not an incredible amount.

The big difference comes from the fact that the bushing allows non-axial displacement, which the material provides both the "spring" and damping action. With a bearing, any non-axial displacement is transmitted directly to the chassis (think rigid body) or something breaks.

 

If you are concerned with keeping the bearing clean there is an AD in Speedway Illustrated for a company that makes seals specifically for rod ends.

 

GSpeed R states it pretty well. The sphericals will allow a more precise and cleaner motion without putting any input from bushing windup or possible bind. On the otherhand they don't have much provision for wear or absorption or isolation of the energies that don't really need to be transmitted to the chassis. Take the spring and shock out of a car with bearings and you should bea able to easily move the control arms and hub fully through it's range of motion by hand with spehricals. You won't be able to do that with a rubber system. A rubber system can have some give, especially when worn that might even be able to let the arms move out of their natural geometry travel due to deflection. Some folks use urethane as a mid point between rubber and bearing as there is isolation but less deflection however it often has increased wear and bind issues as well. In my garage, my street/occaisional lapping day car has fresh rubber bushings after I took the urethane off all but the sway bar and my dedicated racecar has urethane and I would like to put sphericals in a few spots on the racecar if money and rules allowed. For the street, I personally wouldn't consider sphericals on control arms (my rear sway bar came with them but sway bar linkage is different) but that is my choice as I'd think you would be truly hard pressed to find a real performance difference on the street and you could find a list of negatives.

Lots depends on the geometry as well. The rear suspension on a 240SX is a clusterf&*^ of bushing bind and the racers I know have found great benefit using sphericals to get rid of the bind. When Koni was working with Chrysler on the Plymouth Prowler, the car was a study in nasty frequencies and harmonics that bit by bit they got sorted out. The car used 20 inch stiff performance tires, rode low on relatively stiff springs and had a rather flexy aluminum frame with no roof for structure so it was always vibrating. In pre-production I was told you almost couldn't read the speedo because everything shook so bad. There was a lot of finger pointing as to what was causing the issues but at one point I heard that there was so much rubber bushing bind in the rear suspension that it had over 120 lbs of force and the car could nearly stand up on bushing bind alone if you took the springs away. That was a car that they developed a lot over time and got much better but ride quality complaints were very common on early Prowlers due to the cumulative effects of lots of things.

 

Thanks for the posts Lee and G speed, they really helped out with my decision. I found that prowler story funny- the forward design often brings negative consequences, makes you wonder why corporations release products without truly knowing the functionality untill someone complains... As for harmonics I'm going to keep to my reggae loving ear, and stick with a steady beat. (Hows that for an analogy?!) After thinking and help from your posts, I'm going to go with 50/50. For the control arm I will go with the rubber. For the caster/camber I will go with the metal. I already have the comptech so thats a plus too. Thanks again!

 

http://progressauto.com/products/trick.html

Here;s the other style of Bearing sets that we are now carrying as well.