Adj. uca help handling?

[miketexass788]

I know you need one of these to fix your pinion angle, if your lowered alot. But will my car benefit handling-wise with one? I have bmr lca w/brackets, adj. panhard bar, and h & r sport springs.

 

[Kaldar142]

Yes, i noticed my car took bumps and uneven pavement much smoother, everything felt smoother / tighter

 

[sqidds]

Depending on what UCA you have they can hurt suspension performance, help suspension performance or hurt and help suspension performance.

An example of help/hurt is the Metco upper. I have one and it has a nice feature which is that it will “twist” in the middle. This is a nice advantage because as the axle articulates the UCA is not resisting the axle movement and allows the axle to articulate freely. The downside is that because the axle can articulate freely the effective wheel rate (suspension resistance measured at the wheel which is made up of spring rate, roll bar, bushing deflection and geometry) is reduced compared to having a UCA that will not articulate.

That being said you don’t want to have your wheel rate comprised of bushing deflection if you can help it. But that is how the car is designed. If you get a UCA that freely articulates with no bushing deflection/resistance your wheel rate will decrease and at 10/10th load you will be short on spring and or swaybar rate.

In a perfect world if you switched to a articulating UCA you would want to increase your rear spring and/or swaybar rate.

 

[miketexass788]

Depending on what UCA you have they can hurt suspension performance, help suspension performance or hurt and help suspension performance.

An example of help/hurt is the Metco upper. I have one and it has a nice feature which is that it will “twist” in the middle. This is a nice advantage because as the axle articulates the UCA is not resisting the axle movement and allows the axle to articulate freely. The downside is that because the axle can articulate freely the effective wheel rate (suspension resistance measured at the wheel which is made up of spring rate, roll bar, bushing deflection and geometry) is reduced compared to having a UCA that will not articulate.

That being said you don’t want to have your wheel rate comprised of bushing deflection if you can help it. But that is how the car is designed. If you get a UCA that freely articulates with no bushing deflection/resistance your wheel rate will decrease and at 10/10th load you will be short on spring and or swaybar rate.

In a perfect world if you switched to a articulating UCA you would want to increase your rear spring and/or swaybar rate.

So a bmr adj. uca would be good if I planned on getting larger sway bars and better springs?

 

[sqidds]

So a bmr adj. uca would be good if I planned on getting larger sway bars and better springs?

If the bars and springs you are getting are sold as sets (set of 4 springs, set of 2 bars) it can be assumed that the front and rear are spec’d out to be balanced. If you were to add a UCA with no resistance to twisting to the mix the wheel rate of the rear wheels would decrease and the front and rear of the car would no longer be balanced. It could be possible to get that balance back if one or both of the swaybars are adjustable but it would take testing in a controlled environment to be able tell if the needed range of adjustability is available.

 

[DusterRT]

I just can't see how much of a difference the bushing material of the UCA can really make at the wheel..I mean, yes, technically you're right, but I really have to wonder just how much it would change the effective rate at the wheel that's what..30+ inches away? It's not like we're talking rock crawlers that are articulating their axles 45 degrees over boulders..given the positioning I would think the LCA's would be much more of a consideration for this sort of thing.

 

[Kaldar142]

While on-topic of UCAs, right now I have a CHE adj. with poly bushings.

Do you think it would be beneficial to switch to a spherical/rod end type uca? I would also upgrade the rear end uca bushing mount to steedas spherical bushing.

 

[sqidds]

While on-topic of UCAs, right now I have a CHE adj. with poly bushings.

Do you think it would be beneficial to switch to a spherical/rod end type uca? I would also upgrade the rear end uca bushing mount to steedas spherical bushing.

For the track it would be great. They make a hell of a racket though.

 

[Kaldar142]

Don't care about noise, but would it be worth it to upgrade to rod end over poly?

 

[SoundGuyDave]

I went from poly/rod to all rods in the rear suspension, and there is a noticeable difference in feel! I can really sense when the rear is doing weird things, but the downside is that EVERY little rumble, whine, etc is transmitted directly to the chassis. My S197 goes from the garage to the track and back, but after about 90 minutes or so on the highway, the assorted whines can start to wear on you. Between all the rod ends (UCA @ body, LCA both ends, PHB both ends, bump-steer ends) the prothane motor mounts, and front control arm bushing inserts, I can distinctly identify the rear gear, the transmission and power steering pump all whining away from inside the cockpit. With stock mufflers but no cats, under cruise conditions, I think it's actually quieter behind the car than it is in it... Put it on the track, though, and you cease to care... The car feels very tight and predictable. I'm also probably going to do the axle-end Heim joint over the winter, to get rid of that last bit of compliance in the back.

If you felt the difference between the stock rubber and the poly bushings, it's another order of magnitude going to rod ends. There is absolutely NO give to them whatsoever.

 

[Kaldar142]

Hmm... i think i will go ahead and upgrade them then. As long as i keep them the same length, i won't have to re-adjust my pinion angle, right?

 

[Bizzyb0nes]

I have the UMI spherical uca, J&M spherical lca's and spherical phb...its my daily...really not bad at all...i wouldnt hesitate to do it again

 

[miketexass788]

If the bars and springs you are getting are sold as sets (set of 4 springs, set of 2 bars) it can be assumed that the front and rear are spec’d out to be balanced. If you were to add a UCA with no resistance to twisting to the mix the wheel rate of the rear wheels would decrease and the front and rear of the car would no longer be balanced. It could be possible to get that balance back if one or both of the swaybars are adjustable but it would take testing in a controlled environment to be able tell if the needed range of adjustability is available.

My plan is to use bmr sway bars, k member w/ a arms, adj uca, and their lowering springs, to add to my bmr suspension now. You see any problems?

 

[Kaldar142]

I wouldn't use BMR lowering springs, not much of an improvement in handling... Go with Steeda or H&R springs

 

[marksti]

I wouldn't use BMR lowering springs, not much of an improvement in handling... Go with Steeda or H&R springs

As long as its not the Steeda ultralite springs

 

[Sam Strano]

My plan is to use bmr sway bars, k member w/ a arms, adj uca, and their lowering springs, to add to my bmr suspension now. You see any problems?

You can do better on the swaybars... I make bars that are both adjustable, and both hollow... Only BMR's front is either of those things. The rear is solid (heavier) and not adjustable (no ability to tune balance).

Their K-member is more drag oriented and I, in general don't trust aftermarket k's unless they have a robust design--and that one does no. Consider all the lateral load you put in the car ends up in the k-member. We'll brace this and that... then run a k-member that looks like it was built from an Erector Set?

Their lowering springs are pure looks. They are basically stock-ish rates. Much softer than any other lowering springs are, and you need to increase the spring rate to compensate for the lesser travel unless you like riding on your bumpstops and slamming onto them.

As for control arms. I have other preferences, but of the things on your list that's what BMR does best.

 

[Bizzyb0nes]

I dont have experience with anyone elses sway bars...but Strano's sway bars are super nice and made a big difference. They even came with new rear end links...when you add up the bang for the buck against various sway bars...i'd say his win...plus he is very patient with annoying callers like myself and informative

 

[Sam Strano]

You weren't annoying!!!!

What Tim forgot to mention was that he's already used the adjustment provided on the rear bar to dial the car in to his liking--something you can't do with a bar you can't adjust.

 

[miketexass788]

You can do better on the swaybars... I make bars that are both adjustable, and both hollow... Only BMR's front is either of those things. The rear is solid (heavier) and not adjustable (no ability to tune balance).

Their K-member is more drag oriented and I, in general don't trust aftermarket k's unless they have a robust design--and that one does no. Consider all the lateral load you put in the car ends up in the k-member. We'll brace this and that... then run a k-member that looks like it was built from an Erector Set?

Their lowering springs are pure looks. They are basically stock-ish rates. Much softer than any other lowering springs are, and you need to increase the spring rate to compensate for the lesser travel unless you like riding on your bumpstops and slamming onto them.

As for control arms. I have other preferences, but of the things on your list that's what BMR does best.

Tell me more about your sway bars. How will easy is it to use these sway bars to balance your car? Prices on a set of front and rear?

 

[alloy6ix]

As long as its not the Steeda ultralite springs

Why is that? Any one else feel free to chime in on this.