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Whiskey11

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Thank you. I am big on this, because I'm an engineer. Modifications, for the most part, cannot be done in a vacuum. As an example, lowering the rear messes with the suspension geometry. Stiffer springs require stiffer dampers. Adjustable panhards or Watts linkages re-center the axle, brackets fix the lower trailing arm geometry, and adjustable third links (or CV-equipped driveshafts) fix pinion angle. (I still need to do that last part.)

I'm slowly accumulating parts for another round of mods aimed at improving reliability and MTBF.

The stock driveshaft has a CV joint in the middle of it. It does not fix pinion angle, it only mitigates the issues of NVH associated with the pinion angle being too far out with U-joints (at both the transmission side and the axle side). With a lowered ride height you will still have issues with added angular forces on the pinion bearings causing them to wear out sooner than with optimum pinion angle.

I also disagree with the "one suspension company" mentality. All that does is ensure that your suspension is compromised in the direction that Whiteline, or BMR, or Steeda or whomever wanted the bias to be. Usually that compromises handling for ride and only marginally stiffer car setup. That's great if it works for you, but it doesn't for me. Besides, I like a good challenge. See my choice in SCCA class for that! If it was easy it'd be boring!
 

sheizasosay

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Why did you choose a non-articulating LCA for a handling-oriented setup?
 

Sky Render

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Why did you choose a non-articulating LCA for a handling-oriented setup?

Because magical Whiteline amazingness bushings...

or something...

I'm curious too though...

What are you two talking about? Plenty of people run Whiteline LCAs for handling. And I don't want rod ends because I drive this car on the street daily.
 

sheizasosay

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While the Boss 302R might come with the poly LCA's, the Boss 302S come with rod ends. The R was designed with the intent for Continental Tire/Koni "Grand Am" race specifically. I don't know why it comes with them. I wonder if the race teams change them or keep them.

The Boss 302R is the replacement for the FR500C and the Boss 302S is the replacement for the FR500S the way I understand it. I have always understood the "S" to be more of a hardcore race car.

I'm not trying to jack the thread. It's a good thread and laid out nicely. And I'm not trying to argue.

I thought this was all old news though. And I'm not trying to sound like a know-it-all, but what I posted has been challenged and I'm either right or wrong and it's laid out for discussion.

There are 3 major players in regards to bushings IMO: deflection, binding and NVH.

Deflection or deformation happens on soft material. Stiffer bushings fix this at the cost of NVH. The stiffer the bushing, the more added wheel rate (non-linear) you will get once the joint articulates and compresses the bushing.

Binding occurs when a bushing is compressed due to joint articulation meeting resistance from lack of range of motion from the joint. An articulating joint fixes this. Not all are equal.

A heim won't bind or deflect because it is both hard and freely articulating. NVH is the worst.

Rotojoint, J&M street extreme, Johnny Joints are all attempts at free range of motion with less NVH.

This is what I have learned. When you see something incorrect, feel free to elaborate.

Besides all those "details", someone with skill can drive around it. We all know of good drivers beating those with cars that outclass the other in all departments. If you can yoke your car like a pro then those bushings might not be a big deal. But that doesn't change the impact that the bushings and joints have on a vehicle regardless if the driver can work with it or not.

Fire for effect
 

sheizasosay

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I wasn't suggesting a heim. Any one of those three I listed like the roto joint...etc would be ideal for dual purpose.

I guess I just don't understand the whiteline product. Reading and looking at it, I get that it is free to spin in the housing, but I still don't see articulation without compressing the bushing. Maybe if I had one in my hand I would understand better. When you look at, we will say a heim, and move it around it's blatant. I can't see that kind of movement with the Whiteline. I wish there was a video of one with the mounting bolt through it moving it around its entire range.
 
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modernbeat

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...Rotojoint, J&M street extreme, Johnny Joints are all attempts at free range of motion with less NVH...

Having used those types of joints, all of them added a LOT of NVH compared even to poly. But, they are free moving joints with no more friction than the sticky grease adds.

In my experience they are perfect for a competition car, but miserable to live with in a dual purpose or street car.
 

Sky Render

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I wasn't suggesting a heim. Any one of those three I listed like the roto joint...etc would be ideal for dual purpose.

I guess I just don't understand the whiteline product. Reading and looking at it, I get that it is free to spin in the housing, but I still don't see articulation without compressing the bushing. Maybe if I had one in my hand I would understand better. When you look at, we will say a heim, and move it around it's blatant. I can't see that kind of movement with the Whiteline. I wish there was a video of one with the mounting bolt through it moving it around its entire range.

This is the closest picture I have of Whiteline's LCA bushing:

17%20Whiteline%20Bushing-L.jpg


It's difficult to see, but there are slots or "voids" around the circumference of the bushing. They allow the bushing to deflect a bit. So you are correct that the deflection requires some level of deformation of the bushing, but it is designed to do that. Contrast this with the very large voids found on the OEM bushing, which allows bushing deflection only in the "up and down" directions:

16%20Stock%20Bushing-L.jpg


As I said before, I drive this car over 10,000 miles a year on the road. It is my daily driver when the weather isn't bad. I hate clunks and squeaks from my suspension, so I went with what I felt was the best poly bushing design on the market.

I highly recommend the Whiteline LCAs for anyone who wants a stiffer bushing without a huge increase in NVH.
 

Vorshlag-Fair

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I'll weigh in because we've tried SO many different UCAs and LCAs on our two S197 test mules + customers cars we've worked on and tracked.



LCAs:

  • The stock LCAs are heavy, flimsy and come with super soft bushings. They can and do add to axle hop and a mushy rear suspension
  • Spherical bushings are great for a race car but suck on the street. Bang, clang, pow!
  • Typical polyurethane bushed LCAs can add some bind, but not nearly as bad as in the UCA arm position
  • We have installed various Ford Racing arms, Steeda billet arms, Whiteline arms and others.
  • The Whiteline LCAs work very well. They are adjustable in length, and don't add any bind to the rear suspension because of their "magic" bushings. Scoff all you want, but it isn't polyurethane. They are an elastomer that they've developed, not just the "red 95A poly" that everyone else uses.
  • An alternate LCA is a GOOD IDEA, and we recommend the Whiteline LCAs for both street and track cars.
  • While you are under there replacing this arm, don't forget the LCA relocation brackets! These are a low cost, high reward upgrade that adjusts rear suspension geometry that gets negatively altered when these cars are lowered (and they SHOULD be lowered).

We installed these Ford Racing Boss 302-R non-adjustable spherical LCAs on this Boss302 LS, and it worked well on track



UCAs

  • The stock unit is a soft rubber bushing on the chassis side and another on the axle side
  • This upper arm has to articulate a LOT more than the lower arms, and is more susceptible to diagonal rotation and potentially bind (with a poly bushing) of the rear axle when moving over bumps or under cornering.
  • This upper arm's joints really needs to be all rubber or spherical, as polyurethane will add bind here. We've seen the bind translate into "ripped" rubber axle-side rubber bushings, when poly was used up top.
  • We had poor luck with DelSphere bushed upper arms, poly arms, and have settled on two options for dual purpose cars: stick with stock (or the smaller rubber bushed UCAs) or go spherical.
  • Many of the spherical bushed arms don't have tight clearances to the bolt and make noise simply from poor design and fit.

Left: The Boss 302-R upper arm just has a smaller rubber bushing. Middle: The Multi-Matic spherical upper is a work of art. Right: OEM axle side bushing destroyed

We've used "JohnnyJoint/DelSphere" bushed UCAs and panhard bars. These are supposed to be the best of both worlds on paper, with the quietness of a poly bushing but the freedom of dual axis movement of a spherical. In practice they suck, suck, suck. Made lots of noise from day 1, and even with adjustments to the joint they always clank and bang around as bad or worse than the all metal sphericals.


Even after making proper bushings and changing the rear bolt to fit this DelSphere joint, it still makes too much noise

So that's my two cents. Disclaimer: While I push some brands more than others, we sell almost all of the options listed. We also race what we install, and street drive them, too. There isn't a "one size fits all" solution for everyone when it comes to the upper and lower arms: you need to look at your requirements and pick the right solution for your car. If you want our advice, feel free to call or e-mail at [email protected]. We might even recomend something we don't sell.

Cheers,
 
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Sky Render

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The Whiteline LCAs work very well. They are adjustable in length, and don't add any bind to the rear suspension because of their "magic" bushings. Scoff all you want, but it isn't polyurethane. They are an elastomer that they've developed, not just the "red 95A poly" that everyone else uses.

Whiteline's bushing material is proprietary. I call them poly bushings because I believe that they use some sort of polyurethane. However, it behaves very differently than polyurethane.

Whiteline calls their bushing material "synthetic elastomer." It is basically a non-newtonian fluid. At lower speeds, it is more compliant and acts like rubber. This gives it a near-stock feeling when driven on the street. At higher speeds and shock loads, it is stiffer, making it behave more like polyurethane.
 
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BMR Tech

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Great thread Sky, I have been following it.

As for the UCA and the issue of using a Poly-Bushing.....on paper, the negatives that have been discussed for eternity online and at the course, are definitely worth mentioning.

That being said, real-world results are often times better than paper, and often prove otherwise.

My personal favorite combo of parts, for handling duty....is a spherical differential bushing and a Poly UCA Bushing. This ensures you have the articulation you want, and the little bit of absorption of NVH.

At the end of the day, there are people all across the globe that have cornering set-ups, utilizing Poly Bushings in the UCA System. Sometimes people are more concerned with axle stability and pinion angle adjustment, than a "little" bit of binding and roll stiffness induced by the Poly Upper - then again; what if they are using the stock diff bushing?

So, pick the parts you want.....use them, and change them accordingly if they do not meet your wants and needs. Testing is the only true way to come to realization, of what parts will work and what parts will not, for your specific combo.
 

Rehagen Racing

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FWIW - we run the urethane version of the Ford Racing rear LCA on all our cars. The heim joints transfer WAY too much NVH. There is no major benefit that we have found.

just an FYI, for those that do not know. The 302R is a homologated racecar to run grand am, and the 302S is intended for world challenge and Nasa. The 302R is in an essence more "hardcore", but lacks the downforce and aggressive look of the 302S.
 

BMR Tech

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FWIW - we run the urethane version of the Ford Racing rear LCA on all our cars. The heim joints transfer WAY too much NVH. There is no major benefit that we have found.

just an FYI, for those that do not know. The 302R is a homologated racecar to run grand am, and the 302S is intended for world challenge and Nasa. The 302R is in an essence more "hardcore", but lacks the downforce and aggressive look of the 302S.

Good to know.

If you have ever used it, have you guys ever noticed any ill-effects from using a higher than stock durometer bushing in the UCA system? (aka: UCA with a polyurethane bushing)

If you don't mind sharing, what do you commonly use for the UCA, and what is your preference?
 

sheizasosay

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FWIW - we run the urethane version of the Ford Racing rear LCA on all our cars. The heim joints transfer WAY too much NVH. There is no major benefit that we have found.

just an FYI, for those that do not know. The 302R is a homologated racecar to run grand am, and the 302S is intended for world challenge and Nasa. The 302R is in an essence more "hardcore", but lacks the downforce and aggressive look of the 302S.

Do you have to run the LCA's that come on it from the factory due to rules?
 

sheizasosay

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Having used those types of joints, all of them added a LOT of NVH compared even to poly. But, they are free moving joints with no more friction than the sticky grease adds.

In my experience they are perfect for a competition car, but miserable to live with in a dual purpose or street car.

And you tried the J&M Street Extreme joint? Not to be misconstrued as the "polyball" that they offer. I ask because I've had both and heim jointed LCA's and to me, the street extreme joint was what I liked most.
 

Philostang

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I'm glad sheizasosay brought up the distinction in what J&M offers. I have not tried the Street Extreme joint, since it wasn't out when I used their products. I did run the polyball LCAs and was very fond of them. I had them on the car for two years when it was a daily driver (70 mile round trip commute) with 1/2 dozen or more track events/year.

When they came off the car I was surprised that they were in such good shape (replaced in favor of full-spherical arms). I didn't think the polyballs added much of any NVH. They definitely reduced wheel hop. I installed them in the pits at a drag strip, so I had a chance to do back-to-back comparisons on the same day. The difference over stock was huge, but given the crap they put in the car in 2006, that shouldn't come as a shock to anyone.

Best,
-j
 

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