Fox upper control arms

Because they make money on them, and many people who mod Mustangs really have no idea why they do they things they do. They just think Aftermarket stuff must be better.

The issue is Ford's design introduces a lot of bind. Then you have the mindset that rubber bushings are sloppy, so lets stiffen them up with urethane, and you just make the bind worse and uncontrolled, which can lead to snap oversteer.

The herd mentality is also strong. Hop on Facebook and make a post stating you want to keep your quad shocks on yoru car and see what happens. You'll get 100 posts laughing at you telling you to throw them in the trash and buy aftermarket arms with the stiffest bushings you can find. Nobody wants to actually listen about the correct way to modify a suspension. (which unfortunately is expensive).

The best Fox Mustang rear suspensions do away with the Quadra-link setup and convert to a 3-link, or 5-link setup. With a panhard bar setup you can even try a Poor-mans 3-link setup. Hop on youtube or google and you'll see a ton of info on these setups. EricthecarGuy did an awesome series on installing an entire Max Motorsports suspension setup on his fairlane. I've got most of it on my car other than the torque arm (for now).

But...what are your actual goals with the car? You don't need a torque arm to cruise to local car shows. In fact, the NVH increase from one may be a discouraging factor.


To Add:

It's also no secret that Fox Mustangs became famous by going in a straight line. A lot of the aftermarket reflects that as does the interwebz echo chamber.

It's also no secret that crappy movies have made popular the idea that one suspension setup for the track means it is SuperReallyAwesomeSauce on the street.

:tard:
 
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As others have said just stick to rubber/poly mounted arms. However I like the spherical bushings that press into the axle housing and an adjustable upper with a poly bushing on the body side. This is so you can properly set pinion angle and eliminate bind. That’s what’s on my car and there was no noticeable difference in nvh from the spherical bushing. Some people say the spherical stuff wears out quick on the street from dirt and debris but I’ve head them on for at least 10k miles and they’re as tight as when I bought them
 
Because polyeurethane bushings don't break and bind. That's what 95% of modified Mustang suspensions have. If you are running an SCCA race full out, you MIGHT notice a difference with a spherical to correct the binding issue. On a street car, hell no. You'll never notice it. Buy a quality part, grease it well, it will be fine. I bought my car in 1999, and the control arms I have on it came off the car I had before that. So that's about 23 years on the same set of Steeda polyeurethane bushing control arms. Ken's Cobra has the same control arms put in a few years later. Both sets have well over 100,000 miles on them. My car pulls a 1.6 60' on polyeurethane bushings.

Kurt
 
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Because polyeurethane bushings don't break and bind. That's what 95% of modified Mustang suspensions have. If you are running an SCCA race full out, you MIGHT notice a difference with a spherical to correct the binding issue. On a street car, hell no. You'll never notice it. Buy a quality part, grease it well, it will be fine. I bought my car in 1999, and the control arms I have on it came off the car I had before that. So that's about 23 years on the same set of Steeda polyeurethane bushing control arms. Ken's Cobra has the same control arms put in a few years later. Both sets have well over 100,000 miles on them. My car pulls a 1.6 60' on polyeurethane bushings.

Kurt
 
I run the FRPP replacement uppers with rubber at each end and MM heavy duty LCAs. It digs a little better in a straight line and no real increase in NVH. The biggest difference people feel on street car is probably not the arms themselves, but the replacement of the old worn out bushings.
 
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The real problem is so many do not understand the terminology. "Bind" is misleading. The problem is articulation. It's something that ALL cars will see. Drive your car's 1 rear tire onto a 2x4 piece of wood. There is articulation. The rear axle housing is not parallel to the rear bumper at this moment.

The stock bushings are so soft, they will comply with the tilting of the rear housing. So will a heim joint.

A poly bushing will not so the rear NEEDS to tilt, the arm will follow and since the stiff poly bushing will not comply, it will try to twist the mount. This will be a problem on any 4 link rear suspension, a mid 1 sixty foot drag car, a road race car and even a stock 4 cylinder.
 
To Add:

It's also no secret that Fox Mustangs became famous by going in a straight line. A lot of the aftermarket reflects that as does the interwebz echo chamber.

It's also no secret that crappy movies have made popular the idea that one suspension setup for the track means it is SuperReallyAwesomeSauce on the street.

:tard:

Couldn't have said it better myself. This is exactly what is going on.

Kurt
 
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The real problem is so many do not understand the terminology. "Bind" is misleading. The problem is articulation. It's something that ALL cars will see. Drive your car's 1 rear tire onto a 2x4 piece of wood. There is articulation. The rear axle housing is not parallel to the rear bumper at this moment.

The stock bushings are so soft, they will comply with the tilting of the rear housing. So will a heim joint.

A poly bushing will not so the rear NEEDS to tilt, the arm will follow and since the stiff poly bushing will not comply, it will try to twist the mount. This will be a problem on any 4 link rear suspension, a mid 1 sixty foot drag car, a road race car and even a stock 4 cylinder.

And yet, Steeda managed to put 10 Cobra Rs at the top of the pack in IMSA in the mid 90s with poly bushings. No, they don't articulate perfectly, but I'm not pushing my car anywhere near as hard as they were back then.

Kurt
 
just installed Sphericals from LMR into the upper Axle housing ..was an easy install and they work fine ..no aditional noise, .frame bushing is still poly...but hard to say if this is a upgrade to the Polybushings I was running befor ?? just did it to spend some money and find out..:doh:
 

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just installed Sphericals from LMR into the upper Axle housing ..was an easy install and they work fine ..no aditional noise, .frame bushing is still poly...but hard to say if this is a upgrade to the Polybushings I was running befor ?? just did it to spend some money and find out..:doh:

Any input on your impression of how it rides would be appreciated.

Kurt
 
And yet, Steeda managed to put 10 Cobra Rs at the top of the pack in IMSA in the mid 90s with poly bushings. No, they don't articulate perfectly, but I'm not pushing my car anywhere near as hard as they were back then.

Kurt

My reply has NOTHING to do with what Steeda did. Many fast drag cars used South Side Machine bars too which didn't have a poly bushing, they used a solid bushing. So they all rotate along their axis but the twisting is the problem.

The fact is solid has zero articulation and poly has a tiny bit more. Tilt it as little as 5 degrees and something has to twist 5 degrees. Either the flimsy arm, the bushing, the soon to be oval bolt hole or the mount need to follow the rear housing.

How hard a car is driven, how fast it is, has also nothing to do with this. Just drive 1 rear tire onto a 5" high speed bump and the rear axle is no longer parallel with the rear bumper. That is the problem, even for a stock 4 cylinder.
 
Just to be clear are we talking about the axle side of the control arm or both the upper mounts? Since my first post here an on another forum the
answers are about 50-50 as to using poly vs rubber.
Are we talking about a race car?
This is a great discussion and you have also stirred the pot on another web forum. The more you ask the bigger the percentage of answers, many from people who have never driven on a track, don't own a race car but may get a 'little' aggressive on city streets. The crap on my car has been on there for 50k (+-) and I am an aggressive driver, stock upper style with (as advertised) higher durometer rubber at the chassis side, I replaced the rubber on the housing with whatever I don't remember, 50k and still going strong!
So if it ain't no race car just get some quality stuff (MM comes to mind) install it correctly and get on down the road.
Now if it is a race car the only advice I am qualified to give is - the faster you go the more money you spend-
 
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My reply has NOTHING to do with what Steeda did. Many fast drag cars used South Side Machine bars too which didn't have a poly bushing, they used a solid bushing. So they all rotate along their axis but the twisting is the problem.

The fact is solid has zero articulation and poly has a tiny bit more. Tilt it as little as 5 degrees and something has to twist 5 degrees. Either the flimsy arm, the bushing, the soon to be oval bolt hole or the mount need to follow the rear housing.

How hard a car is driven, how fast it is, has also nothing to do with this. Just drive 1 rear tire onto a 5" high speed bump and the rear axle is no longer parallel with the rear bumper. That is the problem, even for a stock 4 cylinder.

So the axle isn't parrallel at 5 degrees of speed bump; So what. Does it really handle worse? I just pulled my Steeda upper and lower control arms off last year. Those things are welded as tight as any other control arm on the market. I don't see any metal fatigue, no cracked paint, etc. If the control arm twists a little bit, but somehow has no sign of it after 23 years, who cares? 23 years, and I don't have any oval bolt holes. I know what you are saying, but it is a theoretical argument that doesn't hold true on street cars.

Kurt
 
Just to be clear are we talking about the axle side of the control arm or both the upper mounts? Since my first post here an on another forum the
answers are about 50-50 as to using poly vs rubber.
UCA - use stock rubber on the axle side.

View: https://www.youtube.com/watch?v=Cll4TElmwnk

Round or square UCA's & LCA's will not bend or break. They do not need to be adjustable for street use.
Tokico 5-way adjustable shocks will do the job of fine tuning the ride.
 
I don't care if it's 99 vs 1. It's a plain fact that a suspension must have some compliance for articulation. BlownGT
s solution from BMR uses factory upper bushings. This will have compliance for articulation. As for your STeeda arms being strong. Yes, they are strong so the tilt will NOT happen in the arm. It will either happen at the bushing or if the bushing is strong enough, like most poly, it will FORCE the mount to articulate. This is when the mount cracks, breaks off the car or the bolt hole goes oval.

If you are having trouble understanding this. Think of a ladder bar car. They have zero compliance for articulation. Just like a door. You move the top, the bottom moves with it. On a ladderbar car, you move the right, the left must move too.