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Mega Modding Braking, Suspension & Steering

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    Posted: Aug/26/2013 at 7:44am
Mega modding a 71 Javelin: Steering, Braking, and Suspension

Some are familiar with my original thread 65" Wide Track Javelin Build, and found it interesting along with a bit of confusion. Not that they lack understanding, just a lot of information that got mixed or changed along the way. This thread is a mostly straight forward compilation of my ever progressing setup.

My changes to the front suspension & steering will leave few parts 100% OEM. Though, will have a fairly factory appearance.

The lower ball joints, beefed up upper control arms & strut rods, and springs are kept within oem fit and function, which can be replaced with parts made for the model and year of the car.

Though the suspension hump, sway bar setup, lower control arm, upper ball joints, spring saddle (Perch), and the strut rod have modifications that either change dimensions or their original operation, or look stock by hidden features.

Here is my vector chart of my finalized mods for maximized wheel and tire fitment.

Top vector chart is my own planed setup, with GM truck tall ball joint welded on top of the UCA, with .200" ~ .250" spacer. Note this option has much better numbers all the way around for best performance, while keeping camber curve minimal.



Vsuspension data

After time, my plans morphed into a custom hybrid Mustang II type based on an AMC suspension, just by customizing things to work together with wide wheels and tires, and maximizing drop effect to 4".

The modified AMC lower arm is just shy in length of the Mustang II lower arm. It was purely by coincidence. You can use stock length lower arms, but your limiting the sweet spot (Minimum camber gain) within a shorter range of travel, and limiting wheel / tire clearance.

Here is a screen shot of my design on vsusp.com











Though AMC upper arm mounting height is perfect for keeping stock length upper and lower arms, when the control arms are properly spaced between the Mustang II spindle. Unfortunately for other Mustang II suspensions types, most all keep OEM Ford upper arm height and distance (ratio) from LCA, which limits suspension compression to about 1", thus the max drop on most Mustang II suspensions is limited to 3", in conjunction with a 2" dropped spindle.

If there is incomplete information in a section, it is because I have yet to acquire a specific part, or decided on an option. Once I have completed the pending sub project, the missing information will be added to the appropriate section.

Each section will cover what was done, along with a bit of theory.

Sections:

What's with them GM clutch pedals *Completed*
Had to explain why some noticed my pedals in various images.
GM brake pedal has the same ratio and length as AMC brake pedal.

Spring compressor DIY *Completed*

*LCA & UCA lightweight micro boxing tweaks *Mostly Completed*
Simple lightweight mods to make them robust under extremes.

Poly Bushing Madness *Completed*
Easy peasy fit and function is not what it seems.

*Informative* So, a 2.5" drop is not enough?
What can you do, if your slamming an AMC stock suspension.

Modding spring perches *Completed*
Works with both Mustang II and stock spindles

Installing a Ford updated SN95 rack and pinion (2.5 turns lock to lock) *Completed*
Works with both Mustang II or when using stock spindles with Pacer steering arms.

Modding SN95 Mustang steering shaft *Completed*
An inexpensive steering shaft for using a rack & pinion setup

Modding SN95 Mustang GT / Cobra Hydroboost & Steering components *Mostly Completed*
My customised installation of a Ford Hydroboost. Direct bolt in with minor mods. BONUS: Added a link to an optional C-III power steering pump install, for a modernised OEM style serpentine belt setup.

S197/S550 Braking, WTF! *Half Completed*
What I'm doing to fill in them blasted 18" wheels.

Modding 13-14 S197 Calipers to fit S550 14" Rotors *Completed*
Expanding the gap between the pads for thicker rotors, and some wee tweaks.

Modding Ford Power Steering *Completed*
Stuff you can do to increase performance from your power steering. BONUS: Making SN95 rack tie rods as good as, or if not better than a modern GT500 tie rod. (Something Ford took 5 years to figure out after my quiet idea)

Shortening a 68 AMX key-less steering column *Completed*
A simple option with standard steering columns 

Modernising factory suspension's castor *Half Completed*
Works with both MII or stock spindles

Beefing up camber *Completed*
Works with both Mustang II or stock spindles

Upgrading sway bar installation *Mostly Completed*
Optional - Works with both stock or a modded suspension

UCA on steroids *Mostly Completed*
Optional - Works with both stock or a modded suspension

Stabilizing strut rod & lower control arm performance *Completed*
Optional - Works with both Ford and AMC strut rods (requires 2 piece bushings)

Mustang II forged spindle installation *Completed*
Optional - If unable to obtain Pacer steering arms. (Requires customised brake installation)

Modding Suspension Humps *Partially Completed*
My unique option for modern big wheels and tires

Hybrid customised rear suspension mod
A mix of odd suspension mods that work together as one without restricting each other in function.

Setting up for track (Tie rods & Camber)

Specifications


Edited by 304-dude - May/04/2020 at 1:44pm
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/26/2013 at 8:06am
Modding spring perches



This is basically from an early 2000 mod that I found online, so I am making the legend live on, though nobody now these days seems to be running such a mod.

Here is a vector graph on why it works so well on stock AMC suspensions. Note, that the limit of travel is only for track perposes, but can be done on the streets. Just you will find some camber gain above the travel limit.s




Update: I decided to scrap my 1/3" upper ball joint spacers that I created for the stock suspension. The spacers were to use proper angles with Mustang II spindles. Using stock ball joints in conjuction, may allow the suspension go into lock up of the steering, when in the extreme upper positions, like in heavy cornering or going over large bumps.

I will be modding my upper Mustang spindle arms to allow GM truck upper ball joints to make a proper swap with the Mustang II spindles. They are the equivalent of Corvette C5 ball joints, but have better mounting and have built In spacing for the shorter distance between upper and lower arms of the spindles.

You wonder what is the point? Well, there are a few factors. Cost of rebuilding, spring options, and the most important... lowering the suspension to be stiffer during body roll. By making the lower arms more flat (parallel to the road), G forces act more against the body than the suspension. Thus less body roll.

Some have used lowering plates to lower the car, but the suspension still remains as it was. I will cover 3 options that will lower the suspension without need of lowering plates, and they all come from changing the spring perch.

NOTE: The first two options below may require some rolling the perch bottom edges outward, on both sides below the convolution pad, which is smooth along the radius. Once done the perch will have a wee more room at the ball joint at tight angles. The oposite side has a pronounced stop indentation for the coil end to seat. It does not need any rolling of the bottom edges, but you may need to remove 1/2" from your aftermarket spring coiled end (a wee nub) to seat. It will not effect height or spring rate.

Below shows the lower edge roll out of the ball joint facing part of the perch at the open area of the control arm. Do not confuse the opposite end as it does not require the rolled edge, and will be mounted wrong if facing the ball joint.




Cheap mod #1 (2" drop)

Use existing springs and graft AMC spring perch ends to Ford perches. This is only cost effective if you have a cutting wheel and know how to weld. You will need to heat the AMC spring perch to remove the center pin for use with the modified Ford perches.

Cheap mod #2 (2" drop)

Same as above but replacing your old OEM springs with new replacements.
I used HD 70 Hornet springs for this setup.


Cheap mod #3 (Custom drop)

Heat up the AMC perches to remove the pins, and use them in 71 to 74 Mustang / Torino perches and replace OEM springs with aftermarket Ford springs. The amount of drop depends on spring rate linear or progressive.

The picture below is to give an idea of how close the tire is to the trough. It is about .660" closer, as I haven't added the required ball joint spacers for the Mustang II spindle, to even out the spindle height difference, and possible seizure of the spindle's turning ability by its clearance. So, the tire is roughly .750" closer to the trough than it should be with all else being stock. Spring is set at 9.5" compression height. Assuming a stock AMC upright, with spindle attached, should be in the ball park of 2-1/4" from the bottom trough with 14" standard rim tires.



All the above mods have poly bushings as a cost effective option. Since the suspension is lowered, a small modification to the sway bar links will need to be done. Shortening by swapping out a shorter long bolt, and cutting the sleeve to allow the sway bar arms to be parallel with the frame while the car is stationary, also the new suspension must be settled before doing so.


Here is an additional mod to relocate the perch inward if needed for adding about 1/2" tire clearance. I did notice I will need to spread out the bottom below the rear seat, like I did with the front, to add more pivot clearance. Also will need to adjust the sides at the back half, as they pinch in on the poly bushings slightly. Once I adjust the spacing, I will place Teflon washers between the poly bushing ends to keep squeaks at bay.








Edited by 304-dude - Oct/04/2019 at 3:55pm
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/26/2013 at 8:59am
Installing a Ford updated SN95 rack and pinion steering
(2.5 turns lock to lock)




This info has been updated to the best rack and pinion Ford created for the SN95 body Mustang, which brings the best steering performance you can have on your car.

Cardone part number 22-2000

Gosh only if I waited longer I could have installed one. But have no fear... I included an easy mod to make steering slop go away like the Cobra rack above if using earlier Ford racks.

One option which I had a link at one time, to have a custom torsion bar made for replacing the stock one, which I show in my Modding Ford Power Steering section.

The other main difference in the late Cobra R rack is the valving and spring setup, to make it feel stiffer like manual steering.

Many Cobra R guys prefer to use a solid u joint coupler instead of a rubber biscuit coupler. I did a check with load, and found it too loose for competition. So I removed the rubber biscuit by drilling out the crimped ends of the retaining pins that hold it to the body. Then I bolted the two ends together as one. If I thought it out earlier, I would have just used a longer steering shaft section to weld to the rack input coupler that is made for custom shaft installs.

OK, I did not make a template to recreate my custom brackets and rework of the drivers side motor mount.

Some have posted in other threads on this forum about using 3" x 2" steel pipe as it is an easier option than to do all the work involved. Also, if using AMC spindles, you must upgrade to Pacer steering arms, or customize with cut steel tubing for proper length and placement.

You need a new or rebuilt 1998 to 2004 Mustang GT rack (It comes with inner tie rods already installed) and corresponding outer tie rod ends. They are long enough to make proper alignment.

I decided to make brackets, and just laid the cross member flat and C-clamped a few aluminum plates to make up 2" of space needed for the brackets. I obtained an 8" cut of 4" x 4" steel pipe. It did well for creating mounting brackets, as there will be extra material to hold in place when cutting, and if by chance you should error in cutting.

From there you can measure how far each 2" segment to the bracket will need to be for clearance. Example: Butting against an eccentric tab, or angling a mounting wall up about 45 degrees on the driver's side. I also made sure I had enough width and height on each bracket for rack mounting adjustment about 4" x 3" mounting pad worked well.

Use the measurements to cut out a card board representation of the bracket. and carefully aligned it between the rack and cross member. This way you can see what needs to be trimmed or added before cutting the steel pipe. Believe it or not, I had measured and cut out my brackets in a few hours.

I knew it would be difficult to cut a perfect piece for fitment, so I purposefully cut all lengths about 1/8" longer and ground down areas for a close fit. Having extra material helps as the cross member is bowed at the mounting face.

The key to the brackets is to make sure their mounting face is parallel flat if possible. Using a solid aluminum mounting kit, will correct any non-linearity. It is a must as perfect alignment can only be done with a proper jig setup during welding.

Once they are welded in place, you can align the racks tie rods to be the same distance from the cross member's ends. Then using a marker though the bushing hole, marked the point of where to drill for mounting.

Critical Information:

Align the tie rods parallel with the lower arm with steering straight, and strut rod with at least 1.25" of open thread at the lock nut end. Once everything is mounted in place, adjust the strut rod til only 2 threads are protruding from the lock nut. It will give proper loaded Ackermann angle and added caster for proper steering, once tie rod alignment is done.

When mounting the rack, be sure that the inner tie rod pivot is the same distance and height from the center of the eccentric bolt, as is the steering arm mounting hole is to the lower mounting hole of the spindle's mounting to the lower ball joint. It is critical that they match to keep minimal bump steer.

Most likely you will need to obtain a tie rod spacer adapter kit for Mustang rack installs. It may be a bit longer than needed, so cutting some of the straight bar between coupling ends will be needed, before welding the two couplers together. Once the adapter spacer has been shortened, it will allow proper bump steer on a simple rack install using original tie rods for the rack unit... Unless you prefer to mega mod, and do the truck tie rod mod that I have done.

Here is a link... https://www.speedwaymotors.com/Inner-Tie-Rod-Extention-Kit-Speedway-Mustang-II-Manual-Rack,8066.html

The image shows two couplers connected, and gives the impression only one is supplied.




Below is some extra pictures to show placement and orientation. Notice that I notched the bottom of each arm to allow the bracket to fit in the lip of the cross member.





Here is a shot of the hydraulic lines for the rack. Had to make a couple of wee bend additions to clear or point a wee better. The sway bar is dropped on the passenger side, so it looks like there is not enough clearance.




Edited by 304-dude - Aug/21/2019 at 8:35am
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/26/2013 at 9:23am
Modding the 2001 Mustang GT Steering shaft



I used a 2001 Mustang GT steering shaft assembly, a basic Ebay item that runs about $20.00 as my steering shaft.

I ended up cutting off sections to be swapped around for final fitment.

The rubber seal and bearing fits well within the 71 on up steering column bracket that mounts to the firewall. Just put a little grease round the ball edges and press in with your fingers. It will stay in place as it is pressed between the firewall and the bracket. Notice the welds to show which segments were swapped.

Note, I will be removing the rubber biscuit from the steering coupler and making it solid for more precise and positive steering. Though road feel will be more noticable.





The pictures below show both the rubber biscuit coupler and solid shaft mod, by taking out the rubber biscuit and bolting the two sections together.





Edited by 304-dude - May/18/2017 at 6:13am
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (1) Thanks(1)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/26/2013 at 9:43am
Shortening a 68 AMX key-less steering column



Above is a mock up of parts that were cut and reassembled to show my first shortening attempt. You may make out the cuts along the integral mesh crush collar. Actually the mesh crush collar is all you need to remove on the outer tube. Just cut where the mesh starts on each end.

As for the inner tube, you will need to remove a segment slightly shorter than equal length. As when you cut the inner tube the bottom segment should slide into the upper segment. You can make alignment marks before cutting so you have no issues with proper look. As for the shaft just cut off above the shaft where it is pined into a small diameter pipe.

Once you have the column parts welded you can assemble and cut off what protrudes from the round clamp that holds the internal spring at the end. The Mustang GT shaft segment fits nicely into the pipe of the steering column, it should be welded to the column as it will couple right to the Mustang shaft at the firewall.








Edited by 304-dude - May/17/2017 at 4:47pm
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/26/2013 at 10:17am
Modernising factory suspension's castor



After looking at the upper ball joint location compared to the lower ball joint I found that the static castor angle is negative. It seems to be inherent to the design AMC had chosen since 70. To me it seems that they took some Ford information about changing the angle for the upper control arm but did not adjust pre 70 trunnion design at the fender locations. Seems like they just cut out and replaced the hump leaving old geometry intact.

Even though the static geometry is negative, the angle at the upper ball joint is very much positive. As the upper arm is tilted with the front bushing higher than the rear. Which allows the upper ball joint to wear at the sides during operation. If the ball joint location was moved 1" inboard towards the fire wall, the wear would be top side, and least prone to show wear as movement with suspension travel would be in line.

The picture below has been modified to reflect the change in upper control arm location. Note that in both pictures maximum adjustment has been done to the strut bar. Also note the change between the ball joints from upper and lower pictures. The bottom picture has a true static positive castor, so no need to adjust the strut bar to maximum to get +1 castor at best and cause binding. Once neutral adjustment has been set to 14.25" at the strut mount, the lower ball joint pivot should be a whisker forward allowing for 2 to 5 degrees positive caster.



By modification of the suspension hump and changing it's mounting location. A number of hidden features make such a modification worth while, and they are...

○ Positive caster is static by default

○ Spring leans away from tire (Gives a wee more clearance for wider treads)

○ More room for higher flow custom header designs

○ Widening track (a longer lower arm must be used)

○ Zero bump steer with SN95 rack and pinion steering


I completed moving one hinge. To remove the stud bracket at the wheel well, all you
have to do is drill out the 6 spot welds along where the hinge bracket mounts. Cleaning with a wire wheel helps make them noticeable.

I need to have a 1 inch tab welded to the end of the mounting flange the hood bolts onto. This will offset the -1" towards the firewall.

Cut the seem section at the cowl and fire wall. I will still need to modify the lower cowl from under the rubber seal down to the fire wall. Using the contour that dips, I will deepen the dip to allow for hinge clearance when closed.



Drill holes for shifting of the studs locations.





Here is the space created for shifting the upper suspension hump.




Edited by 304-dude - Dec/04/2017 at 10:32am
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/27/2013 at 8:52am
Beefing up camber

If you look carefully at my picture in the section about installing a SN95 updated rack and pinion. You will see that the eccentric tabs on the cross member have been strengthened with reinforcing welds along the back side of each tab. This will keep stress cracks and round outs from forming. Even if you have less than 70K original miles, at least one tab of the 8 in all will have some cracking and some round out. Making sure all tabs keep the eccentric steady and secure before doing the reinforcing welds is important. The picture should speak for itself. I am sorry I did not take a picture of the hair line crack that was fixed during the process. Using a wire wheel on a hand drill will allow proper cleaning, so you are able to visually inspect.

Also, you can cut 1/8" steel section to fit between the tabs for a stronger hold, and then drilled for a preset lower arm distance. I will be going that route to replace my eccentrics.




Edited by 304-dude - Dec/04/2017 at 10:33am
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 73hornut Quote  Post ReplyReply Direct Link To This Post Posted: Aug/27/2013 at 9:21am
What about repositioning  the ball joint 90* in the upper control arm?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Aug/27/2013 at 9:41am
You can try with modding a CF suspension, but you are loading up the inner side of the upper arm. There is a reason for centering the ball joint.

I did not want to make this mod a comparison to any after market bolt on. As far as I know none correct AMC geometry without changing upper control arm mounting. One thing, you can use a CF suspension as an addition to my mod, as I am allowing AMC suspension components to function without any modding. All the trickery is done on the body.

Unfortunately, this is an option for those who want to modify a daily driver or customized AMC. So very few will try to incorporate such a change to their runners, as it would require a bit of body work and paint.

If you take notice, most of my mods are fairly clean looking. Not quite stock, easy for AMC'rs to identify yet difficult on everyone else to know any better.


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Installing Mustang II spindles



Believe it or not, there is not much to do to make the Ford spindles work. Though there are two different routes for the type of spindles used. 7°, which is more stockish when swapped, and have 10° KPI (requires extensive modding), which I am covering as I go. I recommend the 7° spindle, since the upper ball joint is the main mod, outside of reaming the spindle's ball joint stud holes for bigger stud fitment.


To make Mustang II 10° spindles function better than lowered perch stock or 7° variants... further mods are required. You need to look at my suspension hump mod in this thread, found here... Relocating upper control arms, as it goes into full detail on obtaining proper angles, and vector mapping key measurements to find proper drop height with your upper arm at rest angle.

Their height is about .70" shorter than AMC uprights, and use the same big end as late AMC disk brake spindles. Plus you can obtain forged versions which is as stout as you would ever need. The only trouble is the lower tapered hole is small, and needs to be reamed out to fit the AMC lower ball joint. I used a Snap-On 10° tapered reamer that cost me $40.00. They range from $40.00 to over $150.00. I expected it wouldn't last but it has.

Critical Information

Due to the differences with spindle height, when the suspension extends up into 3/4 full compression, seizure of the upper end of the Mustang II spindle at the edge of the upper arm. You will need to use a .330" spacer between the factory ball joint or an early 70 to 67 GMC C2500 truck upper ball joint, K680.

For stock suspension humps (no mods), to get close to factory control arm height at the spindle, a GM truck upper ball joint must be used.

You can go heavy duty with a late 70 on up to 95 GMC C2500 truck upper ball joint K6122. To use it you must ream the upper arm mounting hole as well for fitment, as it has the same 10° taper and diameter as the AMC lower ball joint. Also you must weld in the original mounting holes on the upper control arm and drill out 4 new holes to mount the GM bolt pattern for mounting.

For myself, I will be modding my suspension humps, due to lengthened lower arms for 10° KPI spindles. I will be using the K6122 ball joint, and after some deep thought, I will modify the upper arm to allow the ball joint to mount from under, instead of from on top, shown in my pictures. Please refer to my UCA on steroids section, as it shows how what mods are needed to install the ball joint from under the UCA.

Note: Due to slight design changes between 67 to 2005, there are 3 differences between how your ball joint may mount with GM types.

Some have updated tooling to make a larger radius foot print for newer trucks. This made the ball joint upper and lower shells protrude enough for a 5th mounting hole dead center at the front.

So even if you obtain the correct part number, depending on the manufacturer and if it is old or new stock, the part may not fit without upper arm modification to the front mounting radius of the down turned lip. It requires cutting, reshaping and welding... See my UCA on steriods section. I suggest doing the mod, as you never know which ball joint fitment you may get with previous 96 ball joints.

My upper ball joint of choice for installation is the K6122, When mounted on the top of the UCA, the taller spacing with shallow pin depth is not an issue, as it gives 10.50" spacing. Loosing .10" from my set measurements, won't be an issue unless, you are trying break auto cross records. Ha!

Since I am installing under the UCA, for my application, I will ream the upper oversized slightly, to drop deeper on the stud for maximum seat depth, which will shorten the distance by .250". When mounted under the upper arm, the distance between the upper and lower ball joints (measured at the top face of the arms) should be around 10.6".

Seems like all the truck ball joints have a standard stud depth, so even having different heights, the thread length on the stud is the major change between them, outside of the ball size and lengths of fasteners given.

As an option, I looked at GM mounting is done and found all upper arms have the ball joint mount on top of the arm, unlike AMC placement, from under the arm. AMC has a slightly smaller diameter hole, but can be enlarged with a grinding stone and drill. Thus no need to modify the arm to allow the newer ball joint foot print. Just manage mounting holes accordingly.





To throw a spanner into the works, manufacturers may taper the pin near the ball. Or add angle by degree offsetting the mounting plate to the ball. Plus, less robust units have a plug plate, that zerk fitting is placed.

So out of the bazillions of part number equivalent ball joints only a hand full will be perfect in fitting my strict requirements. Some are NOS old stock and some are new with different part numbers for 86 to 05 trucks.

If going with 96 to 05 GMC C2500 truck ball joint - K6292, you don't need the 5th hole for mounting, as it may exist on the ball joint, so that particular difference is mute.

The ball joints for the later years are metric at the ball stud. About 1/32" bigger than 9/16". My 71 to 95 fits the metric change over, so being slightly larger than 9/16" it will fit slightly higher in the steering knuckle hole. Very insignificant, IMO.

You will need 1 metric sized lock washer and thick flat washer to cinch up the gap between the longer stud threads, on the GMC ball joints.

As an option, I decided to use a modded 2002 Ford E150 Van rotor. I cut off the rotor from the back side of the hub. It is the most stout hub you would ever want and can be machined at the back to lighten if weight is a concern. Here is a picture with the rotor and spacer installed.




Edited by 304-dude - Sep/26/2019 at 3:14pm
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
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