Dual rod/del-sphere/roto-joint vs dual?

[skulls]

*I tried searching and couldn't find anything...I think this is tech, but if it's not...im sorry*

Im getting ready to install my cortex watts link and torque arm...

I currently have J&M extreme/street lca's (solid bushing at one end and the ball surrounded by poly bushing to give better articulation at the other end)...they are non-adjustable and cortex says I need adj. Lca's.

So now that I am in the market for new adj. Lca's...im wondering if going with a set that has del-sphere/roto-joint but I have the option of going with them on each end or just on one end.

Are the benefits much greater having the articulation joints at each end over only at one end with sold poly at the other end?

Ill being doing some track driving but it is my daily and my way to work is some nice twisty roads....

any information would be much appreciated....

 

[csamsh]

sphericals are always better...can you deal with the NVH and maintenance intervals?

 

[skulls]

sphericals are always better...can you deal with the NVH and maintenance intervals?

That is not my question....im wondering if having a joint that has the del-sphere or roto-joint at both ends offers much greater benefits?

 

[Whiskey11]

That is not my question....im wondering if having a joint that has the del-sphere or roto-joint at both ends offers much greater benefits?

Sure, it eliminates just one more thing that adds spring rate that is unwanted. It also eliminates that much more movement of the rear axle fore/aft and makes the forces hit the tires harder (good and bad).

Although I have to admit, the prospect of running sphericals at both ends of the control arms sounds like a NVH nightmare. Why not run the Cortex arms since you've already got his TA/Watts setup?

 

[Sky Render]

NVH is subjective. I have BMR's poly/rod-end combination LCAs, panhard, and UCA, and the NVH isn't much worse than with full poly bushings, in my opinion.

 

[Norm Peterson]

Once you put one spherical in a trailing link, you've eliminated the majority of the problem. For a second spherical to improve things by much, you'd need to be dealing with more roll than you're likely to ever get while still having a semblance of control over where your car is going.

It is possible to free up a poly bushed joint a little, and you just might eliminate one of the sources of squeaks in the process.


Really, it's when you're fighting for fractions of seconds at some form of timed competition that the value of having sphericals at both ends is worth more than the NVH and maintenance downsides. My opinion anyway.


Norm

 

[skulls]

Sure, it eliminates just one more thing that adds spring rate that is unwanted. It also eliminates that much more movement of the rear axle fore/aft and makes the forces hit the tires harder (good and bad).

Although I have to admit, the prospect of running sphericals at both ends of the control arms sounds like a NVH nightmare. Why not run the Cortex arms since you've already got his TA/Watts setup?

I don't want to cortex lca's because they are rod ends...I like the "in-between" with the del-sphere or roto-joints. I do like my j&m's but they aren't adjustable...However someone else I know says that whennhe installed his cortex t/a and removed his relocation brackets his j&m lca's (non-adj) where just fine...I also have the drive shaft shop's ds with thw cv joint at the rear and they say there is no reason to need anything to fix the pinion angle, the cv joint takes care of the.

I just don't want to get everything installed and then need adjustable lca's and not have them...thusly my original question.

 

[skulls]

Once you put one spherical in a trailing link, you've eliminated the majority of the problem. For a second spherical to improve things by much, you'd need to be dealing with more roll than you're likely to ever get while still having a semblance of control over where your car is going.

It is possible to free up a poly bushed joint a little, and you just might eliminate one of the sources of squeaks in the process.


Really, it's when you're fighting for fractions of seconds at some form of timed competition that the value of having sphericals at both ends is worth more than the NVH and maintenance downsides. My opinion anyway.


Norm

Thank you Norm...I won't ever be fighting for fractions of a second....I just want to best possible thing under my car...if having the second one is only going to offer that sort of advantage, ill probably go with poly on one end.

 

[Whiskey11]

I don't want to cortex lca's because they are rod ends...I like the "in-between" with the del-sphere or roto-joints. I do like my j&m's but they aren't adjustable...However someone else I know says that whennhe installed his cortex t/a and removed his relocation brackets his j&m lca's (non-adj) where just fine...I also have the drive shaft shop's ds with thw cv joint at the rear and they say there is no reason to need anything to fix the pinion angle, the cv joint takes care of the.

I just don't want to get everything installed and then need adjustable lca's and not have them...thusly my original question.

The street version of their LCA's has a poly chassis side bushing and a rod end on the other end... Not a bad compromise IMO.

As for the CV Joint... yeaaaah... I dunno. The forces on the pinion bushing are still going to be at an angle even if there are no power losses through the CV joint or NVH. Given the propensity for the Ford 8.8 to eat pinion bearing bushings, I would just assume get the pinion angle RIGHT then assume the CV joint wont allow the pinion bearing to get screwed up.

 

[Sky Render]

I assume you need adjustable LCAs to correct pinion angle because the torque arm does not allow you to do so?

 

[dontlifttoshift]

With a torque arm, the LCAs will only adjust wheelbase and thrust angle.

 

[Whiskey11]

With a torque arm, the LCAs will only adjust wheelbase and thrust angle.

This. The only way to change pinion angle on a torque arm is to either shim the mounts on the differential or to shim the chassis mount. Pinion Angle with a torque arm is a bigger PITA but definitely not adjusted with LCA's!

 

[Norm Peterson]

If I'm not mistaken, at least one aftermarket torque arm has PA adjustment capability. You need an adjustable length link between the arm proper and (typically) the upper attachment of the TA to the axle. It's still a true TA even though it includes a link that obviously must be able to pivot at each end.


Norm

 

[Whiskey11]

If I'm not mistaken, at least one aftermarket torque arm has PA adjustment capability. You need an adjustable length link between the arm proper and (typically) the upper attachment of the TA to the axle. It's still a true TA even though it includes a link that obviously must be able to pivot at each end.


Norm

Which unit would that be? Griggs and Cortex are pretty similar to each other in how they mount and neither have that link like that? BMR's might if they ever release it.

 

[Norm Peterson]

Don't recall, just know I've seen one. Can't even say it's for a S197.


Norm

 

[Sky Render]

Then why does he HAVE to have adjustable LCAs? That's kind of the point I was trying to make.

 

[Norm Peterson]

Thrust angle?

Centering the wheels in the opening?


Norm

 

[skulls]

Sorry on the run...but it's the cortex unit.

 

[skulls]

Thrust angle?

Centering the wheels in the opening?


Norm

I believe so...ill call filip and ask.

 

[skulls]

Ok so I talked to Filip...

The t/a does in fact dictate the pinion angle. He says it will maintain a proper pinoin angle but if it's a weird situation and the pinion angle needs to be adjusted you can shim it...but he says that is not more than likely not needed.

The lca's do effect the thrust angle. He says that the t/a shifts the rear end towards the back less than a 1/4" and says most people can never tell and won't effect anything, but adjustable lca's will fix that...but said that I can just used my fixed lca's and drive it and see what I think and if I wanna do adj. lca's I can do it after the fact.

I talked to someone else who has this tq and the exact lca's I have and he says his seems perfect and hasn't seen a shift in in his rear end, or one that he can even notice.

So looks like I will stick to my current lca's and see what I end up with.