CAMBURG UCA - 6.5 Caster???!!??

Hey ya'll,

So I'm in process on a new build of a 2019 TRD OR. Body Mount Relocation Completed. Ordered Fox 2.5 setup from Accutune planning to run at 2.5 inches of lift. 315/70/17 tires.

Trying to decide on a UCA.

Camburg Ball Joint UCA - spoke to a rep at camburg at he said I will want to run my caster at 6.0-6.5 degrees when I align it. That is crazy high! Sounds like a bump steer nightmare. (rep didnt know how much caster is built into the UCA)

Dirt King Ball Joint UCA - spoke to rep at dirt king and he said UCA has 2.1 degrees caster built in, and to run factory recommended caster specs when I align it....so around 1.2 degrees. This is crazy low to me. Sounds like a floaty uncontrolable nightmare.

Can anyone offer some guidance?

I'm used to running 3.0-4.0 caster on my second gen. Have things changed in the past few years? How could recommendations from different manufacturers be so different? Are these UCA built with different goals in mind?

 

You're in the right, you want around 3, maybe a little more. Those reps don't know what they're talking about. I don't even think anything above 4 is achievable with camburg. They don't have much caster built in as far as I know.

 

Thanks man. The camburg rep I think was a little under informed. The Dirt King rep ended up connecting me to their UCA design guy and he seems very knowledgeable - but 1.2 caster still seemed low.

Whats interesting about the Camburg stuff is that if you look through the forums all the older threads say exactly what your saying - they dont have much caster. The new threads are saying the opposite - that they have almost too much caster for any lift below 3 inches, and that people are achieving final caster numbers of 5.0 degrees and beyond. So I'm thinking maybe they changed their design at some point?

 

That's a possibility, I haven't look at them recently. It seems like they overcorrected and went too far the other way. I would go with the dirt king if I were in the market for some new UCAs.

 

I’m running extended length fox 2.5 with Camburg UCAs at an inch and a half of lift. The shop recommended and aligned it at 3.8 degrees of caster, I’ve been really happy with the handling at that setting. I don't know how much adjustability is left in the LCA alignment cams at that setting

It’s my understanding is that Camburg did redesign their UCA at some point to allow for more caster.

 

Thanks for that man. Makes sense - I just talked to a more technical guy at Camburg and he said the Camburg UCA's have 3.5 caster built in. Which is a lot.

So the Dirt Kings have 2.1 built in, and the Camburgs have 3.5 built in.

My concern is this. Even with the cab mount relocation done, will having 3.5 degrees caster on the UCA move that 35 inch tire back so far that I'll be hitting the firewall? I can obviously move the tire forward by raising the caster on the lower cam bolts - I'm just concerned that if I start getting up into the 5.0 degree plus range, the bump steer is gonna get really bad. Any input on that?

Wondering if the dirt kings at 2.1 might be a more conservative option. I'd be curious to know where the guys with the adjustable SPC UCAs that are running 35s have their caster set to on their UCAs.

 

It sounds like you have a decent idea of how the caster works and is added into aftermarket UCAs, by moving the upper BJ back. With the camburg I would be concerned with rubbing issues.

 

Ya man, My instincts are telling me the Dirt Kings might be the better choice.

 

Did you drive it at 5.5? Any particular reaso you brought it back to 3.0?

 

Why do you think too much positive caster will cause bump steer?

If you're trying to fit big tires, ignore the number and max your wheel forward at your LCA. Your caster will be what it is. That's your only chance.

A lot of after market control arms have built in positive caster at the UCA (moves the top of the wheel back), which means that when you max your LCA forward you have a shit ton of positive caster. That's why everyone ends up with +3 to +6 degrees positive.

ETA: Less than 1.5 degrees or so will drive noticeably worse. Adding more positive caster generally doesn't bother people. Some track cars run upwards of 10 degrees of positive caster.

 

Bump*

what’s UCA did you end up with and are you rubbing with 35s?
I’m currently rubbing on my camburg arms with same tires. Looking for solutions besides going down a tire size.

 

Does the built in caster from the uca's move the tire further back towards the cab mount and the lower needs to be adjusted for more caster to clear the tires?

 

I run 6.0-6.5 caster on mine. Drives fine.