Aftermarket Spring Perches Original Mustang Spring Perches Original Brass Bushing Spring Perch

Opentracker roller spring perches:

The concept of putting a bearing in the classic Ford spring perch was first introduced by John Dinkel.  He invented them and I give him all the credit.  Over the years he and I have become friends as we both have the same goal of making classic Mustangs handle better.  The following article was written with his blessing so that anyone who wants to make a set of roller spring perches has the info needed to do so..Many Ford cars, from the Falcon to the Granada, use spring perches bolted to the upper A-arm that serves as a bottom resting point for the coil springs.  The design of the spring perch, through its ability to rotate back and forth as the A-arm travels up and down, allows the coil spring to move with more consistent vertical travel through compression and decompression. 

Free tech on my YouTube channel

The original spring perches found on the early Falcons had brass  bushings.  This allowed for a smooth rotation but had the downside of needing regular greasing and considerable friction between the surface of the bushing and the journal it rested in.  Sometime before the Mustang hit the market in 1964,  FoMoCo decided to replace the brass bushings with rubber ones, which was done primarily to cut costs.  Although cheaper to produce,  the rubber bushing spring perches lacked the smooth, easy turning radius afforded  by the brass bushing. 

If you have ever tried to turn the center shaft in a rubber bushing spring perch,  you know that it takes quite a bit of force to get any movement.   One might  argue that a coil spring provides all the pressure needed to turn the perch and that a smooth turning radius is not necessary, but the problem is that the force applied, from suspension travel, to move the perch prior to the rubber bushing flexing is absorbed by flexing of the spring and shock.  This flexing of the spring and shock results in a less than consistent, less-vertical travel during compression and decompression, and thus puts a lot of stress on the shock, making it wear out sooner.  One option in correcting this issue is to replace the rubber bushing with aftermarket brass bushings, returning the perch to the initial Ford design.  This works well, but without regular greasing, brass bushings tend to squeak.  Another option is to create the roller spring perch.  By replacing the rubber bushings with roller bearings, a smooth turning radius can be achieved and, thus, smoother suspension and drivability without the added friction and squeaking of a brass bushing.  The following is the step-by-step documentation of how I fabricated my own pair of roller spring perches.  This could not have been possible if it had not been for the advice and directions from the original designer of the roller spring perch.  He is a Mustang builder, racer, fabricator, and regular on several Mustang message boards including FYI Ford, and goes by the screen name of “Opentracker”. DazeCars Items for Sale:

Tools required:
MIG or TIG welder, 2” bie-metal hole saw, drill press, saw for cutting pipe, die grinder with grinding stone and sanding wheel, brake hone, deep 7/8” impact wrench socket, ball pein hammer, punch, bench grinder with wire wheel, vice grips, pipe centering block, pipe holding tool, 1” long piece of 3⁄4” square tubing, and, ideally, a shop press.

Hand tools and centering and pressing jigs

Drill press and bench grinder

Brake hone, die grinder, and cutting wheel

Materials required: 
Two modifiable spring perches in reusable condition with mounting hardware, (some aftermarket spring perches use metric shafts that are to small to fit snugly inside the bearing) four HIGH QUALITY R14-rs type bearing 7/8” ID and 1&7/8” OD, and two 3” long pieces of 2” OD pipe with 1/16” walls.
Roller Perch rebuild kits for sale:
I have for sale all the parts you need to convert stock or aftermarket spring perches to roller spring perches. This kit includes two 3" long honed and fitted bearing journals that are ready to weld into the perches, four high quality R14-2RS bearingss, four press in mounting studs, four locking nuts, and for centering washers to drill out the perch body.
Click here to order bearings, journals, or  complete kits.

Note: Some aftermarket perches use metric shafts which are to small to fit snugly inside the bearings. I use ACP brand aftermarket perches or OEM cores as they have the correct shaft size.  

The first thing to start with is a pair of stock spring perches.  Aftermarket reproductions can be purchased or the ones currently in the car can be removed so that they can be modified.  (Always use extreme care when compressing and removing coil springs.)  If using the original perch, make sure that it is in reusable condition.  Examine the center shaft mounts and make sure they are not in any way damaged, cracked, or bent, also examine the main body of the perch for  cracks and/or breakage.  Once the spring perches have been determined to be a sound platform for modification, the process can begin.  The first step is to remove the mounting studs that are pressed into the main shaft.  This can be easily done by placing a small piece of 3⁄4” square tubing approximately 1” long under the main shaft so that the threaded side of the stud is up and the head of the stud goes down through the middle of the square tubing, and then by using a shop press, simply push the stud out.  If you do not have a press, you can put a nut on the end of the stud and tighten it down so that the edge of the nut is flush with the end of the stud, and then drive the stud loose with a hammer.  Once the stud is loose, the nut can be removed and then the nut and the stud can be set aside  for later use.  The next step is to take a cutting wheel and cut down through the side of the main perch body along the edge of the center shaft tubing.  By doing this, the entire shaft  assembly can be removed in one piece.  Set the shaft assembly aside for further deconstruction later in the process.

The current mounting points for the center shaft assembly will need to be cut away to make room for the larger bearing journal that we will be building.  Two washers, one on each side, will need to be spot welded to the main body of the spring perch.  The purpose of the washer is to provide a centered pilot hole for the 2” hole saw that  is used to cut away the side of the spring perch.   I found that getting a washer with a center hole that is just smaller than the pilot drill bit on the hole saw helps to achieve a more uniformly cut perch.  Also, the washer needs  be moved about 1/16”  down from the top of the spring seat, which is done so that the new bearing journal can be mounted into place and still clear a small hump in the inside middle of the spring perch.  Take special care to make sure that the washer is well centered from side to side, this will make for easier assembly later.  Use a drill press and a 2” bie-metal hole saw and drill out each side of the perch.  Be careful when drilling not to apply too much pressure. Without the center assembly intact, the sidewalls of the perch are not very well supported and can bend under excess force.  However, if the sidewalls do bend some during drilling, they can be straightened with a pair of pliers.  It is a good idea to test fit the pipe that will be used as the bearing journal.  It is important that the pipe fit squarely in the perch.  If it sits at an angle, a die grinder can be used on the sidewalls of the spring perch to remove any metal that is preventing the pipe from sitting squarely in the perch.  Once both sides have been drilled out and checked for a square fit, there is not much left of the original perch, however, what remains is a solid platform for the improved perch.

The center shaft will now need to be removed from the center assembly.  This is accomplished by making several cuts the length of the assembly with a cutting wheel.  Once you have cut through the metal, the rubber underneath is no match for a cutting wheel so be extra careful not to cut into the main shaft.   If the perch being modified is an original, then the shaft should be relatively easy to remove from the center assembly once the case has been split.  However, if the perches are new aftermarket pieces then the removal of the center shaft will be more difficult. A long 1/8” drill bit can be used to make lots of holes through the rubber all the way around the center shaft.  This will not completely free up the center shaft but it will make its removal much easier.  (When drilling down through the rubber, pay special attention to not damage the center shaft with the drill bit.)  After much of the rubber has been drilled out, the outer covering can be pealed off of the center shaft by grasping it with a pair of vice grips and pulling.  Any remaining rubber that is adhered to the shaft will need to be cleaned off with a wire wheel.  Once cleaned the shaft can be prepared for the bearings. 

For optimal strength, the bearings will need to ride in the bearing journal directly in line with the sidewalls.  My measurements indicated that the inner edge of the bearing would be about 15/16”  from the outside edge of the shaft. You will need to take your own measurements because there is often times some variation in parts. The next step is to use a punch to dimple the main shaft.  This gives a slightly enlarged area for the bearing to press onto and rest against.  The easiest way to get a uniform line of divots around the shaft is to take at least three raps of electricians tape around the end of the shaft so that there is a clear indication of where to punch.  The build up of the tape forms a lip that the point of the punch can rest up against.  The shaft should then be put in a pipe centering block and the divots can be placed on the shaft about 1/8”  apart with a punch and hammer. If you do not have a pipe-centering block, you can buy one or make one.  I made mine by welding three pieces of angle iron together in the shape of an “M”.  If you have a press you can also make four divots about 1/4" from the line of divots you just made, one on the top, the bottom, and on both sides.  Theses divots are positioned so that the bearing will be pressed over them this will hold the bearing in place more firmly, but can only be done if you have a press.   CAUTION trying to force the bearings over the four divots with out the use of a press could result in bearing damage and premature failure.

It is now time to press the bearings in place.  A deep 7/8” socket works very well for this. When pressing on a bearing you want to put the pressure on the inner race.  If pressure is applied to the outer race, then damage may occur to the bearing.  Place the socket on the press and then set the bearing on top of it.  The shaft can then be slid down into the center of the bearing and into to the socket. Pressure can be applied to the top of the shaft to seat the bearing.  The bearings need to be pressed on so that only about 1/3 of the width of the dimpling can be seen.  This holds the bearing in place but still gives it something to rest against so that in later steps the bearing is not pushed further onto the shaft.  If you do not have a press, the bearing can be seated with several light hammer blows to the top of the shaft, being careful not to damage the shaft.  Once the first bearing has been seated, the shaft needs to be turned over and the same steps are used to seat the second bearing.  If in the process of seating the bearing,  the shaft mounting holes become ever so slightly out of round, that is not a problem because it will help hold the mounting studs  when we press them back in.  However, if the hole becomes very elongated it would be a good idea to replace the shaft.  Excess bending at the boltholes could cause cracks and/or brakeage at some time in the future.

Next the bearing journal should be prepared.  Measure the distance between the outside edges of the bearings on the shaft.  The journal will need to have between 1/8” and 1⁄4” of material past the bearings on each side.  The bearing distance (outside to outside) on this set of perches measured at 2&5/8”, so I cut my pipe 3” long .  This gave me a little bit of extra tubing just in case I needed to square things up with the grinder or a file.  When cutting the pipe, it is best to use a chop saw or a band saw, that way you get a good square cut.  A hacksaw will work, but be careful so that the cut is square.  Do not use a clamp-on pipe cuter!!  I am talking about the type of cutter that clamps itself to the pipe and then you spin it around the pipe until the small wheels to cut through.  The reason you don’t want to use that type of cutter is that it will taper the edge of the pipe inward, making the hole too small for the  bearings.  Once cut, the pipe can be checked to make sure that the cuts are square.  If square, it is a good idea to use a flat metal file and clean up the leading edges, also a round file works very well to remove any inside lip that might have been created from cutting, grinding, and/or filing.  The bearings should be a snug fit in the journal but still slide in without forcing them.  A brake hone can be used to clean up the inside of the journal and make for a smooth fit.

Now that the shaft has its bearings, the journal is ready, and the perch has been cut, we are ready to assemble the unit.  The journal will need to be held in place in the perch so that everything can be welded together.  The easiest way to do this is take a small piece of angle iron and grind down the middle section of the angel so that  it can be used in conjunction with vice-grips or a c clamp to hold the pipe in place.    When positioning the pipe, make sure it is centered and square.  A TIG or MIG welder can now be used to weld the pipe to the perch.  I welded mine on both the inside and outside of the perch walls.  After welding, test fit the center shaft to make sure that the bearings will slide all the way through the journal without any excess force.  It is important to not  put too much pressure on the bearing when pushing it through because, if  you force it through,  there is a chance of damaging the bearings.  At this point I had to get out the die grinder and clean up the inside of the journal where the pipe  was welded to the perch.  After grinding away a very small amount of metal (grind sparingly and check fitment often), I used a sanding wheel to clean up the grinds.  The bearings were then test fitted again and they fit.  The brake hone was then used again to true up the inside of the journal and return it to round.  If you try to only use the brake hone to make the bearings fit after welding, it will probably work, but you will completely wearout the stones on the hone. 

The center shaft  can now be slid into the perch.  Center it in the journal so that there is an equal amount of lip hanging off on each side.  Then take a ball pein hammer and LIGHTLY tap the edge of the pipe bending it in.  Bend in two small sections on one end of the shaft and then flip the perch over and tap the edge on two or three spots on the other end of the shaft.  Once the center section is held in place, you can finish taping the edge all the way around the bearing on both sides, It is a good idea to do a little on one side of the perch and do a little on the other side of the perch, checking often to make sure that the center shaft and bearings are still centered in the journal, until both sides have an even lip holding the bearings and shaft firmly in place. 
The final steps in the fabrication of the perches includes the bending of  the middle section of the journal so that the studs protruding from the end of the shock will clear it.  This is accomplished by placing two pry bars or punches in the shock mounting holes of the  perch and then use a bench vice to squeeze the two shafts together and, thus, bend the journal.  As you apply pressure with the bench vice, it is a good idea to turn the shaft of the perch to make sure that the pressure from bending the middle of the journal is not binding up the bearings. CAUTION make sure that the dent is deep enough on both sides of the perch so that you can get a socket on the nut.  I made the mistake of having one perch not dented enough and it took me over 2 hours to remove the spring compressor and install the shock on that side. 
All that is left now is to press the mounting studs back in the center section of the perch.  This is accomplished the same as removal with a press, or hammer and the 1” long piece of  3⁄4”  square tubing.  If you are reusing the original studs, make sure they are examined for damage and deemed reusable prior to instillation. One trick in installing the studs that might be considered is to press the bolts in, in the opposite direction from which they came out, that way the stud is creating new groves in the mounting hole rather than seating the stud in the old groves.   The perch is now ready for painting and instillation.  There you have it, the step-by-step process for fabrication of a roller spring perch.

  Rebuild Kit

R14-RS bearings.

Stud being hammered out

Perch after the center shaft is removed

Washer welded in to serve as a pilot hole

Drill press used to cut 2" hole in perch

Not much left of the original perch

Bearings can be slid on the shaft for test fitting and measurements

This jig is vey simple to make and makes holding round objects easy

Once the tape is peeled off the shaft is left with a nice straight line of divots for the bearings to seat against

The bearings and shaft resting on the 7/8" socket so that the bearing can be pressed on.  If you look in the picture you can see that more than half of the width of the divots have been covered by the bearing

The journal has been cut, filed, squared and honed so that it can be installed in the perch

It is important to hold the journal in place without bending it.  A small piece of angle iron with the center corner ground flat is perfect for clamping the pipe to the perch.

The journal needs to be ground smooth after welding, and then. with the aid of the brake hone, the surface can be prepared for easy instillation of the bearings.

With the bearing shaft assembly slid in, the leading edge still needs to be tapered in to hold the assembly in place

The width of the journal is too wide for the shock studs to fit past it, but only just barely.

Two long punches can be fit through the holes and used to bend the journal so that the shock bolts will clear.

A bench vise provides consistent even pressure to produce two dents with uniform depth, length, and shape.

The dents now provide plenty of room for the shafts to slide past the journal.

Other Things To Consider:
There have been some concerns expressed  as to the reliability of  using a ball bearing in this application, due to the immense pressure placed on the perch by the spring, and the simple fact that ball bearings are designed to handle pressure on a rotating load.  This is a valid point and warrants routine checks of the perch on a mildly regular basis to ensure that it is still functioning the way it was intended to.  This routine preventative maintenance should not need to be carried out any more regularly than the checks normally made on ball joints, tie-rod ends, or control arms.  The static load capability of the bearing used should be adequate, especially considering the following info:

There are two ways to approach this, first of all with a spring rate of 600lbs, it takes 600lbs of pressure on the spring to compress it 1 inch.  The compression ratio should be a smooth curve sloping up so, in theory, each 1 inch compressed should require the sum of the first compression weight and the last compression rate, which should be greater than the rate preceding it.  Example:  if 600lbs gets you 1 inch, 1200lbs might get you 1" + 7/8", and 1800lbs might get you 1 " + 7/8" + 1/2"  (these numbers are just an educated guess).  To put it another way, it may take 600lbs to go 1-inch, 1400lbs to go two inches, and 2400lbs to go 3 inches.  With all that said, a new spring probably doesn't compress more than 2" during normal driving.  That would make the static load between 1200-1800lbs.  Because these numbers are educated guesses, I will go with the higher number of 1800lbs.  The typical r14-rs bearings will handle a static load between 1100 and 1500 pounds. There are two bearings in each perch, which each take half of the compression load, effectively cutting the pressure in half.  So each bearing is capable of handling 1100lbs and only receiving 900 during brief extreme situations.  Also, during extreme compression, the bearing is moving more and achieving some turning radius, thus transferring pressure to several balls in the bearings. Lastly, due to the continuous pressure from the spring and the give that the spring provides, there would never be any jarring or impact force applied to the bearing.  That is unless the wheel left the ground for a long enough time to allow the A-arm to travel to its most extended point and then come back to the ground with enough force to compress the spring, and at that point, you probably have bigger problems than the strength of a bearing to deal with :)  The other way to look at it is this,  if the car weighs 3000 pounds 60% of the weight is on the front wheels;  in this case 1800 pounds.  That weight is divided among two perches and thus 4 bearings, this means that each bearing is supporting a weight of 450 pounds, which is only 41% of max static load capacity.

Roller Spring Perchs Made by Opentracker and sold DazeCars:
Looking for completed spring perches ready to install? I sell high quality roller spring perches ready to install.  Go to my For Sale Page for pricing and ordering information

Opentracker perches

Here we have it a completed pair of roller spring perches ready for instillation.

Disclaimer on Daze Tech Tips
      I am not an expert in this field. I have performed these modifications myself with very good results. I am passing along restoration and performance tips for the purpose of education.  If you are concerned about reliability or safety issues, I do not recommend that you or any other individual perform these changes or attempt to modify your cars from stock configuration except under your own volition.  I do not assume nor accept any liability for the use of this information or how it is applied.

2013 DazeCars
The words / logos for Ford, Jaguar, Mustang, Galaxie, etc are used for descriptive and reference purposes only. DazeCars is neither affiliated with Jaguar Land Rover North America LLC, Ford Motor Company nor the manufacturers/distributors of Ford or Jaguar automobiles.