Any Body Runnin The J&m Lower Control Arms From American Muscle

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Anyone with any experience in LCA's? Have a 2013 GT and I am also not able to decide which ones to go with. Leaning towards the J&M extreme joints. They seem to have a good design for traction and no binding on corners. Do I need relocation brackets if not lowered?
 
CHE? Never heard of em. Why are they good? Are they adjustable? When I'm aligning the car, are there any special things to be aware of or do I just stick to basic camber, caster, toe adjustments?Thrust angle?How do you know what the right angle is for lcas with a relocation bracket?
 
CHE? Never heard of em. Why are they good? Are they adjustable? When I'm aligning the car, are there any special things to be aware of or do I just stick to basic camber, caster, toe adjustments?Thrust angle?How do you know what the right angle is for lcas with a relocation bracket?

This thread is about rear control arms, no camber/caster/toe adjustments. The reason why they are so good is because the use high tensile steel round tube, custom made bushings not off the shelf, bushings are made by injection mold not pour mold which yields a stronger unit. No grease fittings they are lubed by a sleeve of Delrin. The Delrin sleeve also allows the steel sleeve to float so there is no bushing binding which gives you a smoother ride.

Check them out here.
 
This thread is about rear control arms, no camber/caster/toe adjustments. The reason why they are so good is because the use high tensile steel round tube, custom made bushings not off the shelf, bushings are made by injection mold not pour mold which yields a stronger unit. No grease fittings they are lubed by a sleeve of Delrin. The Delrin sleeve also allows the steel sleeve to float so there is no bushing binding which gives you a smoother ride.

Check them out here.

Bushing bind and bushing friction are completely different things. The use of Delrin will help reduce friction in the bushing as it pivots in the bushing. The problem is that this doesn't solve the problem of bushing bind during cornering. The bushings need to compress and the harder the outer bushings are the less rotation you will have. Polyurethane if properly lubricated doesn't have the friction problem that warrants a sleeve of delrin unless the metal sleeve is poorly machined. The proper bushing design will eliminate for and aft movement of the control arm but still allow the control arm to rotate as the left side suspension moves differently from the right side. That movement is what causes undesired handling results.

This is the testing, design, and solution to properly eliminate true bushing bind not just friction in the sleeve area. Keep in mind when you get to the results section most companies use a 90 or 95 durometer bushing which is considerably stiffer and less compliant.

The control arm bushings found in the Mustang automobiles can have a significant impact on the vehicle’s ride, comfort, handling, acceleration, noise and vibration. When the car leans (i.e., rolls) in a turn, one side of the chassis moves upward relative to the rear axle, the other side moves downward, and the control arms must twist to allow for the axle to articulate. This causes the control arm bushings to bind. If this bind becomes excessive, it will raise the rear wheel rate and produce sudden, uncontrolled, undesirable changes in handling (e.g., snap oversteer).
Ford minimizes this suspension bind by using compliant rubber bushings in both lower control arms. These relatively "soft" bushings help accommodate the necessary motion of the control arms during body roll. However, the rubber bushings do not provide much in the way of forward and aft support, which can cause wheel hop during hard acceleration and braking.
It has become common practice to replace the stock rubber control arm bushings with solid or two piece polyurethane bushings to resolve the shortcomings of the soft rubber bushings. Hard polyurethane bushings eliminate wheel hop, reduce axle deflection, and improve rear straight line grip. However, the downside of common aftermarket bushings such as delrin, steel, stiffer rubber, solid or two piece polyurethane bushings is they prevent the necessary movement of the control arms during body roll, which in turn produces significant binding in the suspension when the vehicle is cornering. The polyurethane bushings also place unnecessary high stresses on the torque boxes, which are the attachment points for the control arms to the chassis. Standard aftermarket control arms do not allow for rotation of the control arm during cornering because of the stiffness of the bushings.
The Solution:
We at J&M Products designed and built a tubular lower control arm which will eliminate the unwanted uncontrolled control arm flex. Round tubing is harder to work with but has many other advantages over square or rectangular tubing. It is stronger in bending, torsion, and also lighter than square or rectangular tubing.
We then solved the shortcomings of the factory rubber and other aftermarket polyurethane and stiffer rubber bushings. This was accomplished with our Patent Pending 3 piece Poly-Ball bushing combination. By spending countless hours looking and dissecting the geometry and the need of the rear suspension we come out with bind-free bushings set up. Our Patent Pending Poly-Ball bushing combination incorporates a very hard inner polyurethane ball which is surrounded by soft socket outer cups. This combination allows the bushing to articulate like a spherical bearing during cornering but the hard inner ball does not allow the bushing to deflect during acceleration giving you great traction during acceleration like solid bushings but remains completely bind free like a spherical bearing during cornering for great predictable traction in the corners.
The Testing:
We built a fixture which simulated a factory control arm mounting and tested how much force was needed to make the control arm articulate (twist) in those mounts and the results where astounding.
Poly-Ball Bushings:
5 degrees of total rotation = 26.1 foot/pounds of torque
7.5 degrees of total rotation = 35.8 foot/pounds of torque
10 degrees of total rotation = 41.7 foot/pounds of torque
Standard 2 piece setup using only 85 durometer bushings:
5 degrees of total rotation = 124.7 foot/pounds of torque
7.5 degrees of total rotation = 156.4 foot/pounds of torque
10 degrees of total rotation = not measurable with fixture. The 1/2" grade 8 bolt twisted in half at 9.2 degrees which was 210 foot/pounds of torque.
 
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I ordered a set of these and they should be delivered today.

Was wondering if J&M could provide any input on this thread: http://www.teamshelby.com/forums/in...e-extreme-joint-upper-and-lower-control-arms/

GT500Tow says:
"The biggest problem with this type of joint is. It has to be adjusted as it wears. If its not adjustable. Then in a very short time of street driving. They start to clunk.

If its a street car. Then i wouldn't run this type of control arm. I would get one recommended for the street. I adjust mine about every three months. Its an 2007 with 10K miles. Just to give an idea of the maintenance required to run these control arms. One big problem is i don't believe the J&M's are adjustable. "
 
I ordered a set of these and they should be delivered today.

Was wondering if J&M could provide any input on this thread: http://www.teamshelby.com/forums/in...e-extreme-joint-upper-and-lower-control-arms/

GT500Tow says:
"The biggest problem with this type of joint is. It has to be adjusted as it wears. If its not adjustable. Then in a very short time of street driving. They start to clunk.

If its a street car. Then i wouldn't run this type of control arm. I would get one recommended for the street. I adjust mine about every three months. Its an 2007 with 10K miles. Just to give an idea of the maintenance required to run these control arms. One big problem is i don't believe the J&M's are adjustable. "

Ours do have adjustment in them but won't have the wear problems the other companies will. The other companies choose to use Delrin or some other type of plastic and we chose to use a very hard polyurethane. The Delrin has had problems for many years with fast wear in suspension bushings which is why most offroad 4x4 suspension builders are going back to the custom molded poly.
 
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Thanks for the very detailed information. Exactly what I was looking for.

EDIT: Got these bad boys installed.. all I can say is :banana: These things are amazing. Get them now!
 
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I just installed a set. Very easy to install- less trouble than a CAI- and great performance gain in terms of traction. Combined with the polyurethane sway bushings in the rear, I am getting no wheel hop at the moment. Just spin. Time for some better tires now! I should note that I have been having "vibration" like unbalanced wheels lately and most of it seemed to go away when I installed these.

I should also note that the front bushings of the OEM rear LCAs I removed (BOTH driver's and passenger's sides) were cracked right down the middle; just three years worth of wear, you guys should be inspecting this! I suspect the V6 cars are okay, but the parts are probably undertoleranced for the V8 powertrain.

Only thing left to do now is replace those rickety front LCAs! Every time I drive over a speed bump or small hole, I hear clanks up front and nothing as the back goes over...the back is nice and tight now.
 
Hey Brian-

I was hoping you could answer another question as you seem to be very knowledgeable about this stuff.

I have plans to lower my stang in the future. I thought I would merely need rear relocation brackets for the rear LCA's and an adjustable UCA.

However, I was told that bind could sill occur if the rear LCA's were also not adjustable.

As you are aware, the Extreme joint LCA's are non adjustable - but I have been VERY pleased with their performance. Do I have to buy adjustable rear LCA's to get a correct geometry when the vehicle is lowered?

Post for reference: LCA relocation bracket adjustment - Mustang Evolution

Thanks.
 
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Hey Brian-

I was hoping you could answer another question as you seem to be very knowledgeable about this stuff.

I have plans to lower my stang in the future. I thought I would merely need rear relocation brackets for the rear LCA's and an adjustable UCA.

However, I was told that bind could sill occur if the rear LCA's were also not adjustable.

As you are aware, the Extreme joint LCA's are non adjustable - but I have been VERY pleased with their performance. Do I have to buy adjustable rear LCA's to get a correct geometry when the vehicle is located?

Post for reference: LCA relocation bracket adjustment - Mustang Evolution

Thanks.

Suspension bind has nothing to do with the upper or lower arms being adjustable. The only time we recommend adjustable lowers is if you swapped out to an aftermarket rear end housing or you are only racing the car.
 
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Thank you sir, that is what I needed to know!

Does J&M make an Extreme Joint Rear Upper Control Arm for the 11-14's?

I can only find them for the 05-10 models.

I've been impressed enough by the LCA's that I'd like to stick with J&M as much as I can for the rest of the suspension upgrades.


Suspension bind has nothing to do with the upper or lower arms being adjustable. The only time we recommend adjustable lowers is if you swapped out to an aftermarket rear end housing or you are only racing the car.