Rear control arm questions.

[Bruce Mohacsy]

I am going to replace my rear control arms and add a pan hard bar this spring. I was going to get the non adjustable lowers and the PHB from Maximum Motorsports but does anyone have any thoughts on where I should get my STOCK uppers from? What bushings do I need to replace on the uppers (if any) or do they come with the bushings on both ends installed all ready? Keep in mind that this is a STOCK motored car with the 7.5 rear end and will be that way probably for the next 3 years.

My goal with these add ons is to just tighten up the handling and freshen up all those tired original parts. .......get rid of the old girls cellulite and tighten up her butt, so to speak.

[ragtopjr]

Bruce are you auto crossing, or road coursing this car?
If not I think the Pan Hard bar is a waste of money, take that money and step up to the adjustable lowers. http://www.maximummotorsports.com/He...1998-P523.aspx
For uppers I would just replace the bushings, and maybe even box them.
Buy their bushing removal /install tool and then before even using it buy a bunch of extra grade 8 bolts because the bolts will be destroyed during the process...

[Bruce Mohacsy]

I thought controlling the side to side axle action would be noticeable for road use. You don't think so? I've never driven a car set up with a PHB so I have no real experience determining whether this mod is appropriate for a road car. I might try some light bracket racing this summer but no track days. Too expensive up here! I have already fitted lowering springs and new Koni's. I'm happy with the ride height. Why would I need adjustable Rear LCA's?

[83gtstang]

I would leave stock uppers, maybe go NOS Ford Motorsport for the bushings. I have heard this due to torque box damage, it's good to have some give, as for the lowers, sky is the limit, as stated above, SCCA racing? If so sure why not, my 85 has a Pan Hard bar, but it was raced for a while for fun. Never cared for it in my street strip car.

[ragtopjr]

I thought controlling the side to side axle action would be noticeable for road use. You don't think so?

Unless you have added a bunch of power, and its priority is leaning towards road course then it is going to be a waste of time, and will also hinder you at the dragstrip.

For a good launch you want easy weight transfer, which is something the PHB is designed to remove(more side to side, but it stiffens everything)...

I've never driven a car set up with a PHB so I have no real experience determining whether this mod is appropriate for a road car. I might try some light bracket racing this summer but no track days. Too expensive up here!

I am pretty light on road race suspension, but if you wanted I could hook you up with Kent in Edmonton who has his calypso fox built for road racing, and runs chump cars as well....

I have already fitted lowering springs and new Koni's. I'm happy with the ride height. Why would I need adjustable Rear LCA's?

Especially if you are planning on doing some drag racing the adjustability may be the difference between being able to launch the car and tire frying extravaganza at castrol.... (Its not likely to be that extreme given the fact that you dont have much motor).

I learned what I have by buying the wrong parts back when there was no other options...

Case in point, my 3600 lb ragtop with the X cam motor ran 13.4 @ 102.9 with lakewood traction bars(which deletes the rear sway bar), with ET Streets this car was consistently breaking stock axles, or leaving with 1.81 60 foot times.

I was able to consistently get 2.0 60 foot times out of street tires, and I am not talking about drag radials, I am talking about Bfg Radial T/A and Comp T/A....

This was all done at Saskatoon which is about .1 to .2 quicker then Edmonton due to elevation.

Once I built the better motor the suspension stayed the same and was road coursed, and auto crossed that way....

I have since upgraded to the LCA's I suggested and absolutely love them!

Now I just need to find a rear sway bar to put back into the car...

[wraithracing]

Bruce,

I would recommend regular stock OEM rubber bushings for the upper control arms and on the rear axle. DO NOT BOX The upper control arms!!!!!

The upper arms need to flex and twist for the Fox rear suspension to work while cornering. This is absolutely required for decent ride and handling on a street car and a road race car. If you drag race your car almost exclusively or the majority of the time you can consider a lot of other suspension options, bushings, bearings etc. Drag racing does not need the twist and flex in the upper arms since the only corners are at the end of the strip and at low speed!

From our previous discussions I believe you want a street car with an occasional run down the strip. Set your car up for street driving the majority of the time and you will be happier than if you set it up for drag racing and seldom do it.

A panhard rod is a major improvement for a Fox both on the street and on a road course/auto cross. The pan hard rod locates the rear axle under the vehicle and limits it's side to side movement. This helps relieve stress and one job from the rear control arms. This allows the rear control arms (upper & lower) to focus on the up and down motion of the rear axle and alleviates binding and stress from locating the rear axle.

How much you can "feel" the difference on the street will depend on how hard you drive the car. Night and Day difference probably not on the street. Take the car to an autocross or and open track and you will definitely "Feel" the difference. The difference and benefit will be there on the street either way, to what degree you experience it will be determined by you and your driving habits.

Trey

[Bruce Mohacsy]

Thanks Trey. As you know by now, I work with a limited budget so I try and make modifications that ACTUALLY make a positive difference than ones that are just considered cool. Thanks as well for reminding me about the stock rubber bushings on the upper control arms. I "hear and validate" the science behind these little beasts! I do like to give the old girl the whip every once in a while and I have noticed the back end behaving a bit uncivilized so I was hoping the panhardbar would help keep the rear axle more in line with the front end when under stress. BTW, I finally got those full length subframes and the K-member brace from MM a while ago. Looking forward to installing those in the spring.

[wraithracing]

You will notice a huge difference once you get the Full length SFC installed. The K member brace helps too with the stock K member, although it's tough to feel the difference via the seat of the pants.

I would recommend getting the SFC installed and go from there. On a Fox body that make such a huge improvement and the difference on a T-top car is night and day!

Good Luck!

Trey

[Quikk86]

Bruce,

I would recommend regular stock OEM rubber bushings for the upper control arms and on the rear axle. DO NOT BOX The upper control arms!!!!!

The upper arms need to flex and twist for the Fox rear suspension to work while cornering. This is absolutely required for decent ride and handling on a street car and a road race car. If you drag race your car almost exclusively or the majority of the time you can consider a lot of other suspension options, bushings, bearings etc. Drag racing does not need the twist and flex in the upper arms since the only corners are at the end of the strip and at low speed!

From our previous discussions I believe you want a street car with an occasional run down the strip. Set your car up for street driving the majority of the time and you will be happier than if you set it up for drag racing and seldom do it.

A panhard rod is a major improvement for a Fox both on the street and on a road course/auto cross. The pan hard rod locates the rear axle under the vehicle and limits it's side to side movement. This helps relieve stress and one job from the rear control arms. This allows the rear control arms (upper & lower) to focus on the up and down motion of the rear axle and alleviates binding and stress from locating the rear axle.

How much you can "feel" the difference on the street will depend on how hard you drive the car. Night and Day difference probably not on the street. Take the car to an autocross or and open track and you will definitely "Feel" the difference. The difference and benefit will be there on the street either way, to what degree you experience it will be determined by you and your driving habits.

Trey

Well said!

To the OP, unless you are drag racing every single weekend and the goal of your car is to be a street driven drag warrior, skip compromising favorable road handling characteristics for a suspension that may run a tad bit better on the strip... Love a MM PHB equipped Fox on the street and you should be able to disconnect it at the dragstrip if you are trying for maximum weight transfer, etc.

[Jerry peachuer]

I have max Motorsports lowers and I also bought my heavy duty uppers (stock OEM ) from max Motorsports as well and I would highly recommend replacing all the bushings related to the control arms
I also have the wild rides torque box reinforcement kit and the stock bolts were replaced with summit racing and were too short for the extra thickness of the reinforcement kit and esna nut so I re called max motorsports and bought there bolt kit and torqued the bolts to 80 to 85 ft lbs
I have the lowers that can raise spring by 2 inches it's perfect to get the common sag out of fox bodies
As far as the panhard it's a nice piece as well but I believe you would benefit with control arms and subframes first it will really tighten things up in the back

[Bruce Mohacsy]

Thanks to ALL of you who posted your thoughts! As always this forum is a wealth of knowledge made available by a bunch of great people. My car wouldn't be a 10th as good if I hadn't joined up.

[P51-Sled]

What Trey said. I followed his recommendation on Max LCA (I went non adjustable) and placed new bushings in the top stock units. Made the world of difference. Car launches great and tracks well.

[qtrracer]

Most of the above commentary is good info. But you have to understand what is being asked of the converging 4-link rear suspension. The uppers are designed to do two jobs: axle roll control and axle lateral control. To do these two jobs the upper arms must "grow" in length and twist as the arms articulate through their range of motion. To accomplish this feat, Ford used soft rubber bushings (to allow growth) and stamped channel upper arms (allows twist). If one uses harder bushings and box the arms, the design is defeated. However, the lowers only do one job; to square the axle with the front track. Here Ford used rubber bushing as well but mostly for NVH. So, harder bushings and/or boxing here does not create the issues such changes would create in the uppers.

The uppers are where the Fox chassis suspension needs the most work. As the arms articulate the bushings/arms grow and twist - but lonely so far before they bind. When they bind, the suspension becomes rigid, wheel rate goes through the roof and you lose traction. In a corner, losing rear traction generally occurs suddenly - called snap over-steer. Believe me when I say this is not something you want to experience on a mountain road.

The best solution is to eliminate both uppers as in the T/A or at least one as in a PM3L; or replace with an IRS, Steeda 5-link or true 3-link. Any of these solutions will transform the handling of the car both in cornering and straight-line performance. Why? Because you eliminate all or most of the bind created by the stock 4-link design. With the above said, three of the above require a PHB or Watts link for lateral control. This is a must for the T/A, PM3L and true 3-link.

But, adding a PHB and leaving both uppers in place will not do much toward decreasing the bind. Moreover, because the uppers define one roll center, and the PHB defines another the two will fight each other. What will this do to handling? Not much a novice will feel, but the car will not be "transformed." In short, think of the suspension as a system: rear pieces must all work together; front pieces must all work together; and both front and rear must work together.

I have no objection to building either the front or rear suspension piecemeal. But just putting a PHB on an otherwise stock rear suspension won't help without the supporting pieces.

[Bruce Mohacsy]

Interesting and I get it. Question:
Have people ever successfully removed one upper control arm and added a pan hard bar?

[Black97Tbird]

Alright, I'll bite: Why isn't everyone getting or making another tool like for the axle side, and replacing the bushings? I've worked on plenty of 8.8" stuff, but never removed the UCAs from the car to look. I really don't see throwing away perfectly good arms because the bushings petrified.

Also, the FMS control arms are sn95 style (and rubber material) bushings, but the arms are the same otherwise. I'm assuming the old Fox bushings are made of wood. Does anyone have a part number for the stock sn95 arms then?

Tom

[Black97Tbird]

Anyone read this?

http://forums.corral.net/forums/94-9...l#post15158330

SUCCESS!!!!! After much research, and pounding of pavement, I have found a solution to the problem. This was near and dear to my heart, as both of my SN95s were exhibiting issues with the UCAs, so I had a little skin in this game.

NAPA has the upper control arm, front bushing. It is part number 267-4460. The issue is that, for some reason, many of the books ONLY list that part number as being good from 79-93. WTFO. American Muscle has a listing for MOOG bushings under part # 88009 the same way. I called them, but they are insistent that it only fits the 79-93 model Foxes. My personal feeling is that they will fit, but I can't prove it right now.

The NAPA part number was the same way. In their book, it was from 79-93. I mic'd my bushing, compared and they sure looked the same. So, I took a chance and ordered two. They fit perfect. Now to be honest here, I ordered in a pair of used control arms, 79-98. I was told they were off a 98 GT. When you look at the listings on the control arms, it says that the they are the same from 79-04, but the 99-04 have a slightly larger hole for the bolt. But these fit, the bushings fit, and they fit on my SN95 as well. (I have only done one so far...maybe next weekend???)

Napa still shows a listing matching the number:


http://www.napaonline.com/Catalog/Ca...460_0131083630


Tom

[Black97Tbird]

another link for moog bushings, a kit for both sides of the arm on rockauto:

http://www.rockauto.com/dbphp/x,cata...OOG_K8637.html

Tom

[wraithracing]

Interesting and I get it. Question:
Have people ever successfully removed one upper control arm and added a pan hard bar?

In the racing circles it's called PM3L or Poor Man's 3 Link. There are many people that have run it in road course racing and autocross when rules didn't allow for a torque arm or other aftermarket setups. Does it work, overall Yes. Is it the best solution, No not really.

Unfortunately as discussed time and time again, the whole Fox rear suspension is a flawed design from a "Good" or "Performance" aspect. Does it work on a stock car and a reasonable power level, Sure! The issue is once we start modifying it the "flaws" and design issues become worse and cause all kinds of problems. The snap oversteer is something the Mustang is famous for and can be very dangerous when it's not expected. Once again the best solution depends on what you really want to do with your car.

From what we have discussed before, a spirited improved street car, I believe the best option for your GT is a set of MM full length SFC, MM lower control arms with a set of OEM upper arms with new rubber bushings on both ends. Those changes alone will make a huge improvement in the ride and handling of your GT. This is a cost effective solution and will most likely be all that you need/want. . . . . Until you start driving the car a bit harder or pushing it more in the corners.

Then you will want to look at a Torque Arm, IRS, 3 or 5 link setup to really transform your Mustang into a Corner Carver.

Trey

[Bruce Mohacsy]

Well said. This is the discussion I was hoping for when I started this thread. I made an expensive "mistake" putting on stock springs and KYB struts before I joined this forum. I didn't like them right off the bat. Almost immediately after joining I learned that people unanimously disliked the KYBs. I wasted a whole bunch of time and money going down that road. LOL!

[wraithracing]

Well said. This is the discussion I was hoping for when I started this thread. I made an expensive "mistake" putting on stock springs and KYB struts before I joined this forum. I didn't like them right off the bat. Almost immediately after joining I learned that people unanimously disliked the KYBs. I wasted a whole bunch of time and money going down that road. LOL!

Don't worry Bruce, we have all learned a lot lessons the hard and costly way! They are generally the lessons we remember the best!

Good Luck!

Trey

[qtrracer]

Interesting and I get it. Question:
Have people ever successfully removed one upper control arm and added a pan hard bar?

I have. But I did it in pieces. I started with stock uppers - then called the M5500-A arms - with harder durometer rubber bushings and the MM non-adjustable lowers. Monroe Formula GPs and FRPP "C" springs. Then I put on the MM PHB thinking that would fix the rear traction and movement issues. It did fix the movement but traction was still terrible, especially throttle on exit (auto-x). After a bit more suspension study (primarily listening at C-C.com) and reading suspension books, I learned that the converging 4-link Ford used on the Fox chassis was a compromise in several places but primarily handling. And the uppers were the primary issue due to bind. At that time, there were the MM and Griggs T/As, and Steeda came out with the 5-link (essentially the uppers of the 4-link are relocated and a PHB is added). I was very interested n the true 3-link and tried to design one based upon s197 parts.

There was a new company - Evolution Motorsport - marketing a 3-link conversion for the Fox chassis - the tri-link. Very compact, light, above the axle, allowing stock exhaust. But it used all rod-end joints and was attached directly to the axle housing. This transmits a lot of NVH into the cabin. So, I purchased a one-off, rod-ended PM3L to test both its usefulness as a suspension piece and the NVH it created.

Now this one piece transformed the car but not until I upped the rear spring rates. You see, there is so much bind in the upper rear suspension that the rear spring rate can be held down; the bind creates spring rate. So those had to be raised - I went with H&R Super Race. Suddenly, I had throttle on corner exit traction - tons of it. But there was so much that it increased front under-steer. But here is the great part; the ride quality improved too. No bind and super articulation means the rear end works over the entire range - smoothly. Before I had the funds to purchase the EvO tri-link, they stopped production. So my PM3L stayed on the car for three seasons; DD too.

[Jack Hidley]

For drag racing use, the PHB will have virtually zero affect on traction. Since it is composed of a single link across the car, with spherical bearings at each end, it can't constrain the suspension motion in any other direction than side to side. It won't help, but it certainly won't hurt.

In a Mustang designed around good street handling, I would install a PHB before I would change out the stock RLCAs, assuming the bushings in them were in reasonable shape. The major reduction in side to side motion in the rear of the car is much more noticeable than the change in improved stability from the RLCAs.

[xctasy]

I vote Panhard rod early on. It has some issues, (like a Panhard rod makes one side of the vehicles axle move to one side, and offers less lateral location, than, say a Watts Linkage as used in the World Rally Escort RS2000's, the Australian Falcon, Alfa Romeo, early RX-7's and the last Live axle SN197 Mustang and Mercury Marauder).

Like these ones



Although a race car set up, in my opinion all Watts linkages need a Michael Mumford modification, like used in the race 1981 onwards GM T-cars and 1983 onwards XE 351C Falcon race cars, still use the stock pickups, but deactivate the Watts rocker on the axle. Back in 1983, 500 hp Group C touring sedans wouldn't steer properly because the upper and lower arms were not the same length, and the traditional Ford production Watts Linkage failed to reduce roll steer because the Watts linkage then added roll center changes to the mix.



There are some long running problems with Watts linkages for exhaust pipe clearance (even worse than the Panhard rod) and the inability for the axle to maintain a constant roll center to relative to the chassis with suspension travel.

In terms of what you can do with the steering gear, axle pickups and the shock absorbers you have, a Panhard rod is hard to beat.

Ford used the Panhard rod to such success in the early Galaxies. Its became the default NASCAR suspension rear end.

As a location mechanism, its high results and easy to do, and as long as you can fit your exhaust through, its cheap too.


The Australians experimented with it in developing the German designed General Motors second series Opel Commodore B's in 1978 (called the V-car internally at GM, which became the Holden Commodore VB), and found it was a brilliant way to tie down a wayward four bar live axle. It makes the transition to oversteer more a slow motion move than a snap.


The Mustang uses the same V-car track width, pickup points and rear damper rates as the German/Australian Commodore, and those old GM V car compacts remain one of the best handling live axle cars around. In fact, the 1978 Fairmont base was the same wheelbase, track, and in later years as the LTD, practically a visual copy of the Opel Commodore B based Senator.




Its little wounder that our more savvy expatriate Aussies bolt up a Panhard rod at first chance.


Like LTDScott

Bold and Underline, Mine!

"Better still, the ride is firm, but not crashy-aftermarket-call-your-chiropractor firm; thanks are due in large part to a heavy-duty set of factory springs, standard on the LX and now available in the Ford Performance catalog as "C" springs. (Chamberlain says they're even heavier than GT coils; an observer noted that the car barely budged after the pair of us had wedged ourselves out of the cockpit for the drive.) The Panhard bar eliminates the snap-oversteer problem the owner claims he discovered while aggressively challenging San Diego's network of freeway on-ramps, but you can still hang the tail out and dirt-track it if you're so inclined. The overall effect is one of solidity, feeling as if carved from a single piece. Delicious and addictive. "

http://vb.foureyedpride.com/showthre...Muscle-Macines

Article http://www.hemmings.com/mus/stories/...feature19.html

Incidentally, the Australian Commodore also used a variant of the US TRW steering rack as a replacement for the old German ZF steering box, so the Aussie 1978-1991 Commodores shared Mustang pickup points and steering gear.





See how similar it is to the Mustang live axle? The shockies are exactly the same, the spring units similar, its the upper links that differ.



The Fox body inherited the powered rack from the Mustang II, but placed it in a better position than in the V-car. The V-cars rear mounted TRW rack suffers roll over steer, the Fox bodies front mounted rack, promotes under-steer, and actually helps remove some of the snap over-steer. It would be a lot worse if it had the old Falcons rear mounted steering gear. The Panhard rod then reduces weight transfer, and this helps transient response under direction changes.

On the dynamic front, the Mustang just needs some GM like compact car tweeks, they both respond to the same things.

[xctasy]

Take Fords first Panhard rod car, the Galaxie and its big bro, the Gal based Mercury Marauder Park Lane.

[xctasy]

My background for last 19 years has been road roughness using a spin off of the GM Proving ground Mays Meter. I used one at Opus International Consultants from 1993 to 2000, and then I made 'my' first one, a single bump integrator Mays meter, in October 2002 with a contracting company.

From 1993 to 2000, I spent 190 000 km in front of a Panhard rod VP Commodore. The Panhard rod bushes wore out once, going up in end play to 0.5" and our road roughness readings went up 20% on rough roads due to the rod banging around. The PHB Is a great bit of kit to secure the suspension.

The advent of the Panhard bar was needed on early development for Aussie V cars, and helps ride control in the rough



Take Fords first Panhard rod car, the Galaxie and its big bro, the Gal based Mercury Marauder Park Lane.



The rod was on the chassis on the drivers side, and on the axle mount on the passenger side.




Under normal ride height, the left and right wheel placement was equal in the gaurds.

Under full droop, the drivers side almost touched the wheel gaurds, while passenger side axle moved 5" off line.


That's what a three bar Panhard rod does, a four bar Mustang and Panhard rod will do it, with a little less movment.

That's about the only negative of a PHR. Its easily the best way to tie a kangaroo down, sport!


The MM PHR set up is a quatum leap on the basic GM set-up, and many steps on from the old GalaxiE based 3 link PHB


Look at it! It won't be ineffectual or do little for your turn in, handling or hurt your ride.