Post adjustable UCA install - are these correct

[cudajames]

Recently installed PST adjustable UCAs, I am not sure I sized the arms lengths correctly - looks like the balljoint is at an angle. just doesn't seem right to me

The car has been in for alignments and drives fine. Nothing from the alignment shop

I have the car partially apart and want to make sure about these? Or put my mind at ease

 

[abodyjoe]

What’s it look like at ride height?

 

[Frnknsteen]

I assume you are talking about the adjustment of the heim joints on the UCA mounts?

What was the specs that the alignment was set to? I would think that would tell you if they are where they need to be. If they are both in too far or out too far, Camber would be off. If one is in or out more than it needs to be, Caster would be off.

I would think you would want to adjust them so you have somewhere between 0-1 degree of negative Camber (depending on how you intend to drive it), and have them adjusted properly front to back to have a good amount of positive Caster (2-3 degrees or more).

 

[MoparLeo]

Just loosen the lock nut and turn the heim joint to align with the bearing.,

 

[Bad Sport]

looks like the balljoint is at an angle. just doesn't seem right to me

That might be because you have the suspension hanging free, put a jack under the LCA and raise it up to load the suspension and see if that angle changes.

I would also want those heim joints 90* to the mounting pin.

I'm certainly no expert on these, lol, but those 2 things jumped out at me.

 

[Frnknsteen]

I would also want those heim joints 90* to the mounting pin.

I thought about that too, but I would think it would be more important to have them parallel to the lower control arm. Not an expert here either though.

 

[Bad Sport]

but I would think it would be more important to have them parallel to the lower control arm.

I argued with myself over that, lol.

You could be correct, I'm sure someone will have the correct answer.

 

[cudajames]

Everyone thank you, I will go back and lengthen the arms to get the balljoint closer to 90 degrees

 

[72bluNblu]

Everyone thank you, I will go back and lengthen the arms to get the balljoint closer to 90 degrees

That’s not what they said. The ball joint should be at an angle, that’s your caster.

The heim joint on the front leg of the UCA seems like it’s excessively angled. That would mean the heim might run out of range as the UCA moves through the suspension travel. If the heim binds up before the UCA hits the bump stops you’ll trash the heim and shorten its life. The heim should probably be closer to vertical. But, you have to check the heim through the entire range of suspension travel. It may be maxed out in the picture, but, that may just be because the UCA is on the bump stop (the travel is also maxed out). It’s not ideal if that’s the way it has to be, but with some cars it may be necessary.

Do you know the actual alignment specs? Because that would definitely help us evaluate those pictures.

That might be because you have the suspension hanging free, put a jack under the LCA and raise it up to load the suspension and see if that angle changes.

I would also want those heim joints 90* to the mounting pin.

I'm certainly no expert on these, lol, but those 2 things jumped out at me.

I thought about that too, but I would think it would be more important to have them parallel to the lower control arm. Not an expert here either though.

90* to the pin isn’t always possible, and it’s not absolutely necessary. But you do have to make sure you don’t exceed the angle range of the heim as it runs through the entire suspension travel range. You don’t want the heim to bind up as the UCA runs through the available suspension travel. Heims have a misalignment angle tolerance, you just have to make sure yours operate within their range.

 

[Frnknsteen]

90* to the pin isn’t always possible, and it’s not absolutely necessary. But you do have to make sure you don’t exceed the angle range of the heim as it runs through the entire suspension travel range. You don’t want the heim to bind up as the UCA runs through the available suspension travel. Heims have a misalignment angle tolerance, you just have to make sure yours operate within their range.

That's what I was thinking Blu. Thanks for clarifying! My thought pattern was that they need to aligned with the plane that the LCA travels in (or at least close) so they don't bind as the UCA goes up and down.

 

[67Dart273]

The simple answer is it looks to me like the heim balls are bound or about to bind. Outer part of heim should be perpendicular to the pin. Moving them should not affect the alignment enough to worry. They should all look more like this

 

[cudajames]

Again thank you for the help - my focus was on the balljoint and not the heims - I will work on those

Here is the last alignment - driver-.5 camber (pass - .6 camber, 7.2 (driver) and 7.0 (pass) caster, .30 (driver) and .27 (pass) toe with cross camber 0.1 camber, 0.2 caster and total toe .58 degree

 

[TrailBeast]

Again thank you for the help - my focus was on the balljoint and not the heims - I will work on those

Here is the last alignment - driver-.5 camber (pass - .6 camber, 7.2 (driver) and 7.0 (pass) caster, .30 (driver) and .27 (pass) toe with cross camber 0.1 camber, 0.2 caster and total toe .58 degree

I would serve you well to grease those Heim joints and get covers for them.

 

[Bad Sport]

my focus was on the balljoint

Right, but they do need corrected.

Did you put a jack under the LCA and raise it some to load the suspension?

If so, did it correct the angle of the ball joint?

 

[cudajames]

I did not - the car is still apart. during the reassembly I will work to correct those. And re-crease them. Never thought about covers - i will also look into those

 

[72bluNblu]

Again thank you for the help - my focus was on the balljoint and not the heims - I will work on those

Here is the last alignment - driver-.5 camber (pass - .6 camber, 7.2 (driver) and 7.0 (pass) caster, .30 (driver) and .27 (pass) toe with cross camber 0.1 camber, 0.2 caster and total toe .58 degree

What is the planned use for the car? And how wide are the tires up front?

I ask because that’s a LOT of positive caster. I’ve run as much as +8 on my Duster, and have been stepping it down since then. I’ve run it at +7 and at +6, and at least for now have settled at +6.5* of caster. Even that 1/2 degree down from 7 makes a big difference.

With wide tires up front (I have 275’s) the additional caster is nice because it overrides the tendency of the wide tires to track ruts and things in the roads. But too much starts to add too much camber on turn in and you really start lifting the car on turn in and upsetting the weight balance. I’ve changed my thinking a little on the positive caster recently- I do still think it’s good to have more than what the stock parts usually allow, even more than the offset bushings usually allow (+3 ish typically) but once you get to 6* or more you really have to evaluate some of the consequences too. I think even for most street cars geared toward handling staying between +5 and +6* of caster is probably better, unless you’ve got 255 or wider tires up front and notice that rut tracking tendency.

As for the heim boots they’re a good idea, especially at the UCA. The UCA heims kind of sit in a pocket there and collect junk. I’ve run my strut rod heims unbooted for almost a decade and like 70k miles on my Challenger without issues, but the UCA heims seem to wear out a lot faster.

 

[cudajames]

I have 215/45s up front - the car will be a street bruiser and I will autocross it.

Front end has been rebuilt with that in mind, thicker t bars, boxed LCA, adjustable struts, greasable pivot shafts, etc etc. , frame connectors and front and rear sway bars

 

[72bluNblu]

I have 215/45s up front - the car will be a street bruiser and I will autocross it.

Front end has been rebuilt with that in mind, thicker t bars, boxed LCA, adjustable struts, greasable pivot shafts, etc etc. , frame connectors and front and rear sway bars

Ok, that makes sense. With 215’s up front though I think you’d be happy reducing the caster some. Like I mentioned it was a big difference just going from +7* to +6.5* as far as steering and handling feel. With 215’s you shouldn’t have tracking issues with the steering, and a less extreme setting should help keep the heims in a good operating range.

On my car the difference between +8* and +7* wasn’t that dramatic. The difference between +7* and +6* was pretty dramatic, to the point I added some back in. On my car anyway it seems like +6.5* is a sweet spot for it.

 

[GMachineDartGT]

Why would anyone purchase an upper control arm that has to be removed to make adjustments? The eccentrics don't offer a lot of adjustment in the grand scheme of things. There are many better choices on the market.

 

[72bluNblu]

Why would anyone purchase an upper control arm that has to be removed to make adjustments? The eccentrics don't offer a lot of adjustment in the grand scheme of things. There are many better choices on the market.

Totally agree. Although most people really don't need an adjustable UCA at all, just one that has more caster built in. If you need an adjustable UCA then getting a "double adjustable" UCA that can be adjusted on the car makes more sense. And if you don't need an adjustable UCA using one with the additional built in caster and that uses a bushing instead of a heim makes more sense. The alignments will be easier because you just use the stock eccentric bolts and the bushings are pretty much hassle free and will outlast the heims many times over.

But live and learn right? I only know figured that out after being hassled by setting the alignment on a set of UCA's I had to adjust off the car. And after wiping out a set of heims after 7k miles of street driving and having to do it again.

 

[DrCharles]

What am I missing here? My Dart has adjustable upper arms with the heim joints, but also the stock eccentrics and bolts. I think the idea is to set the heim joint approximately correct with the eccentrics in the middle of their range, then fine-tune with the eccentrics rather than removing the arm for each adjustment?

 

[72bluNblu]

What am I missing here? My Dart has adjustable upper arms with the heim joints, but also the stock eccentrics and bolts. I think the idea is to set the heim joint approximately correct with the eccentrics in the middle of their range, then fine-tune with the eccentrics rather than removing the arm for each adjustment?

You’re correct, that’s the idea. You should only have to pull the UCA and adjust the heims if you can’t get the alignment right using the eccentrics, ie, you didn’t have the heims close enough to the alignment specs you wanted to finish with the eccentrics.

The first time you install them it might mean pulling the UCA’s an extra time to reset them, it depends on how extreme an alignment you’re going for and how straight your car actually is. They may not be the same side to side, and the more caster you want the less equal the heim lengths will be. Some caster is already built in too, so there’s some margin for error. If you do your own alignments that’s no big deal, if you take your car somewhere it might mean an extra trip because a lot of places won’t touch aftermarket parts they didn’t install.

The only exception to that I’m aware of is the E-body Hotchkis UCA’s. They relocate the front UCA mount for better geometry, but that means you don’t use the front eccentrics. Which means all the adjusting is done with the heim on the front mount. On A bodies I’m not aware of any that do it that way though.

 

[GMachineDartGT]

You’re correct, that’s the idea. You should only have to pull the UCA and adjust the heims if you can’t get the alignment right using the eccentrics, ie, you didn’t have the heims close enough to the alignment specs you wanted to finish with the eccentrics.

The first time you install them it might mean pulling the UCA’s an extra time to reset them, it depends on how extreme an alignment you’re going for and how straight your car actually is. They may not be the same side to side, and the more caster you want the less equal the heim lengths will be. Some caster is already built in too, so there’s some margin for error. If you do your own alignments that’s no big deal, if you take your car somewhere it might mean an extra trip because a lot of places won’t touch aftermarket parts they didn’t install.

The only exception to that I’m aware of is the E-body Hotchkis UCA’s. They relocate the front UCA mount for better geometry, but that means you don’t use the front eccentrics. Which means all the adjusting is done with the heim on the front mount. On A bodies I’m not aware of any that do it that way though.

My SPC arms offer the most and easiest adjustment without removal.

 

[72bluNblu]

My SPC arms offer the most and easiest adjustment without removal.

Totally agree! I have your SPC UCA's on my car and I LOVE them. I think they're even easier to adjust than using the stock eccentric bolts.

But, not everyone needs them. For the average street car that range of adjustment is probably overkill, you can get what you need out of a set of non-adjustable tubular UCA's that have the caster already built in and just rely on the eccentric bolts for the alignment. That makes the whole alignment process a little easier because you only have to work with the eccentrics and not the arms themselves. And I've found a lot of alignment places don't want to touch parts like the SPC UCA's, they don't want to assume the liability. Which isn't a big deal if you do your own alignments like I do now, but for the guy that has a street car and a basic alignment and who just wants to take it down to the local tire shop, it can make life unnecessarily difficult.

To me, if you're going to run around on a set of 15" rims with BFG TA's up front you don't need something like the SPC UCA's. If you're running 15's then you're running 225's or 235's up front at the most, and if you run +3* or +4* of caster and -.5* of camber it'll be great. Now, if you're running 18" rims and 275's up front I've found that I want more like +6.5* of caster and more like -1* camber to tame those tires, which means the non-adjustable UCA's won't cut it. But I'm doing my own alignments and my car isn't exactly using a typical street car set up.