The added caster helps with stability on the highway as well. The factory settings had up to 1deg of positive caster.  With that small amount of caster, the cars will wonder around on the highway, making for an uncomfortable ride. We put in 2.5 to 3 deg of positive caster. It's not a big change but it makes the cars drive bettter. 

 

Like many things automotive, there are different approaches that yield the same result.  I would posit that 2.5-4 degrees of positive caster would be ideal, but as previously stated, is unobtainable with the factory range of adjustment where the best you can hope for is about 1 degree positive. 

However, you can compensate by adding some toe-in, which effectively does the same thing in terms of reducing wander on the highway.  You could run as much as you want in terms of toe-in, but I've found that going beyond 3/16" results in scrubbing and noise during tight turns.

I've found that with 1 degree of positive caster and 3/16" toe in the tracking on the highway is pretty good.  Steering effort with a manual setup is also not increased a tremendous amount.  Dial in about 1-1.5 degress of negative camber and you will have a well handling platform even with the limitations of the stock system, provided all parts are in in good order.  Cost to benefit this is a great setup for the average guy.  Obviously there are benefits to the 50 years of suspension design that has come after the Mustang design was created.  The cost to entry can be a bit steep, but if your goal is to make a 45-50 year old car outhandle modern cars that option exists as well, and a lot of options in the middle. 

devovino wrote:

I would like the car to ride less stiff and a little on the softer side so that may change my spring choice.

less stiff than what?

the stock ride is as soft as it gets . . you can buy sprinhgs that are slightly lighter than the ones i posted but they are full length springs like stock, however, because they are stiffer than stock, they can still be cut a little if you want to lower it.

the 480 spring rate i pisted is the lightest of the "lowering" spring rates i know of and the ride is noticeably firmer thsan stoc but not overly harsh.

imo, the 620 spring rate is too firm for these cars for just general cruising, this includes the heavier cars like the 69 and up fastbacks etc.

you can set your ride height from stock to around 2" lower with the "lowering" springs.
..

Last edited by barnett468 (1/16/2015 2:05 PM)

afnid wrote:

Another question I have is that the adjustable strut rods are used to 1) provide adjustability for front-end geometry, and 2) to provide a free range of motion for suspension travel.

In the process it sounds like you lose a lot of the ride quality because of the road vibration being transferred direct to the frame.

using a hiem joint for the front strut mount transfers a lot of energy to the body which is definitely noticeable when you bumps or potholes.

total control products has some front bushings that are mush fimer than stock but not as form as urethane and they also allow freerer motion which is only really helpful on a professional road race or auto cross car etc . .  maier racing also sells something similar . . the tcp ones are around $65.00, the maiers are a lot more.

   

Last edited by barnett468 (1/16/2015 3:00 PM)

hi

not sure what you mean by behind or in front.

the farther apart the mounting points are on the strut rod the less affect it will have on the caster as the lower arm moves it and down.

unless you are a professional race driver, it is unlikely you will notice a change of caster from the strut rod.

a heim joint adds to body shock, there is no room for opinion, it's a simple fact of physics and engineering principal.

a johnny joint in the front of the strut rod will transfer just as much energy to the body as a heim joint.
.

Last edited by barnett468 (1/16/2015 3:58 PM)

barnett468 wrote:

hi

not sure what you mean by behind or in front.

the farther apart the mounting points are on the strut rod the less affect it will have on the caster as the lower arm moves it and down.

unless you are a professional race driver, it is unlikely you will notice a change of caster from the strut rod.

a heim joint adds to body shock, there is no room for opinion, it's a simple fact of physics and engineering principal.

a johnny joint in the front of the strut rod will transfer just as much energy to the body as a heim joint.
.

lol, thats one of the debates, whether the strut rod pulls/pushes the control arm, but if it rotates around an axis parallel to the chassis, then it's relative position forward/aft never changes.  When it is not parallel it will.

When I say behind or in front, I am referring to the relocation of the strut rod pivot point, the linked page is what I would call behind, it lengthened the rod, most kits I see are in front, shortening the rod.  If stock it is parallel to the chassis, both of these options rotate it away and will cause the arc to now move the ball joint forward or aft relative to the chassis, and may be minscule within the actual range of travel.  But McStang alluded that the positive location of the pivot was an advantage.

No dispute on a hiem joint, the johnny joint has an insulator in it (delrin i think), and is supposed to be considerably smoother.

Heim joints in general are a terrible idea on a street car.  They cause a harsh ride, and they wear out pretty quick too.  There are expensive ones with Teflon lined races that are more durable, but they are expensive.  Your options are:  stock rubber, which deflects quite a lot making for imprecise handling.  Polyurethane, which can cause bind under some conditions, and can squeak like a haunted house if not kept lubricated.  Heim joints, already discussed.  Del-A-Lum bushings, which are a pretty good solution.  They last almost forever if you keep them greased.  They are harsher than rubber, but so is every other option, but not as harsh as heim joints. 

Shock and spring selection also plays an imprtant role.  Suspensions are no diffeent than engines.  Its isn't any one part; its the combination of parts. 

My car has poly bushings, 620 front springs, and KYB shocks all around.  In normal driving on normal roads its fine.  Driving over a fire trail, etc. would be torture.

Wheels and tires are also important to ride.  Lower profile tires have stiffer side walls and produce a stiffer ride.

Just some more stuff to consider. 

devovino wrote:

 Also, does anybody know the size of this nut, as well as the nut on the end of the Strut rod?

7/8 socket should fit both.  The first time I had to remove the LCA nut, I had to use an extender on a breaker bar.  I also got the harbor freight ball joint seperator ($20) after spending WAAAAY TOOOOO MUCH time trying to get the control arms off, once the castle nuts were loose.  Best $20 I've spent on tools so far.
 

afnid wrote:

devovino wrote:

Looks good, I am just trying to stop any ongoing rust and not doing paint/body, but I think I also have a cowl leak and your making that look like a much easier problem to deal with.

 The Ospho has done a real good job of converting the rust, and in most areas I have used Master Series Silver moisture cured urethane as a top coat to further mitigate the problem. As for the cowel, I lucked out and mine were in good shape, I did the ssame process inside there (Ospho and then top coated with the silver). Not sure if you can tell from the picture or not, but I did cut an "access hole" on both side to inspect inside there, I have also seen replacement done through this hole of the hats depending onthe condition of your cowel? I guess it all depends on how far you want to take it?...  https://www.youtube.com/watch?v=dKHn7fFPZoc
[quote888] devovino wrote:I would like the car to ride less stiff and a little on the softer side so that may change my spring choice.[/quote888]
less stiff than what?

the stock ride is as soft as it gets . . you can buy sprinhgs that are slightly lighter than the ones i posted but they are full length springs like stock, however, because they are stiffer than stock, they can still be cut a little if you want to lower it.

Well truthfully, less stiff than a locomotive!... Hahaha, no honestly I have never driven this mustang so I dont know how stiff the ride would have been, so I really have no point of referance? I bought the car as a roller only and starting rebuilding it.Truthfully I say I would like it "less harsh" but in reality, I will be happy with whatever I come out with! I think with all the input I get, and all the invaluable information out there, I will get it dialed in the firs time around. Its not going to be a full time race car, more of a streetable unit, so that is what I am aiming for, something I can take a cruise in and not get beat to death going over small cracks and or bumps.

TimC, thanks for that, I was able to resource that information and I will see if the penetrating oil helped at all. I did actually rent a Ball joint seperator, as well as a coil spring compressor. I did definetly use the ball joint seperator, and it took me a bit to figure out how they came apart, I really had to drive it home to seperate the Spindle from the other parts. I never really got to use the spring compressor as the order I took out the components was backwards, so I ended up just removing the UCA, used a ratchet tie down strap to compress, and it all kinda just "fell out of there", with a little leverage and fulcum. On the passenger side I have it a little more figured, the order of operations that is... trial and error...

Rubber pads not shown.  Not as smooth as a bearing, but way better than the stock pos.  They were ~$108 for the pair delivered to my door..

Now done with the driver side, I was finally able to remove the castle nut that was "frozen" on the  spindle/LCA, as well as the bolts on the strut rods were equally resistant,  and get the suspension torn out.  Same conditon as the passenger side with some rust inside the shock tower, I have run out of Ospho so I just cleaned up the outside of the fender aprons and will have to get some more rust treatment. Maybe today, but big game for us here in the Pac N.W., GO HAWKS!!!
Also, in my "free time" I have continued to remove paint for re-paint, here is a pic of the doors before & after. Metal is in good shape, just a few dents need addressed.
Ready to do the Shelby drop, and begin applying paint before I rebuild the suspension/brakes/steering. I am tempted to leave the passenger inner fender apron off for a bit, makes it easier to access the engine cpmpartment, that is next for prep/paint.

BTW, do I remember ther being a "JIG" floating around that was shared to do the Shelby drop, or do I just buy one from Open Tracker with my upcoming order.?
Thanks Y'all!
DevonNNow its time to clean up this MESS and move forward!
 

devovino wrote:

I am at the point where I am ready to start tearing into my front suspension, and replacing it all with new components. I am trying to figure out what parts are best to use, I did a comparison between Moog and Open tracker parts, and this is what I came up with as a good starting point:

Open tracker suspension part pricing
Front Suspension
Upper control arm:  $225 pair (90 degree zerk, rebuilt shaft kit, welded tab for security)
Lower control arm:  $160 pair  (actually made by moog)
Roller spring perches: $199 (Not really comparable, one of a kind)
Coil Springs:  GT 350 – 1” lower- :  $93.95
                        560 Lb   - 1” lower- : $82.95
                         750 Lb  - Track      - :$ 93.95
Shocks:  Grab –A-Trak  (Nitrogen charged)  $59.00 a pair  ( $59.00 rear pair)
KYB Shocks: Gas-a-just (Very Firm Ride)     $ 90.00 a pair  ( $90.00 Rear pair)
** Bilstein Shocks – Street Valving: $ 164.00 a pair
                                     Sport  Valving: $ 278.00 a pair
                                     Track Valving:  $ 324.00 a pair      (Bilstein Rear Shock:  $ 199.00 a pair)
                Total with highlighted items above: $ 841.00
 
 
 
Moog Parts
Upper control arm made by MOOG part # RK621428:  $145.98 a pair
Lower control arm made by  MOOG Part # CK8035:  $73.78 a pair
Spring perches “non roller” :  13.73
Coil springs  “stock” , made by MOOG :  $59.79
Shocks -  KYB Gas adjust: 32.79 pair ( Front & Rear)
 Total with above parts:  $266.28

There is a bit of a differance in price, just trying to find the best medium. I do like the idea of the roller perches, but are they really that amazing? Would I realy notice the differance>? 

I have had Bilstein shocks on an Pre runner truck I owned, and I know the quaility is great, any feedback here? 

I also plan on replacing most of the steering components as I go forward as well, but thats a differant ball of wax.

I also know you get what you pay for, and only want to do this one time, the right way! Thanks in advance.
Devon



 

I went with the Bilstein shocks and absolutely love them as I had the Kyb gas ajust shocks before and you could feel every bump in the road with those and they felt like you were driving in a dump truck.  I am in the same boat as you are with rebuilding the suspension components.  I just ordered a bunch of new parts but haven't gotten everything yet.  First, I'd recommend any Moog part as I ordered a bunch of Moog products and all of which say "Made in the USA" on them.  I talked to Maier racing and they recommended their Bilstein shocks, which I have and would never go with a Kyb again.  They also said that for a street car with minimal track time to go with the Scott Drake urethane style spring perches.  I also bought Moog lower control arms, great quality, and the Moog upper control arm rebuild kit to rebuild my old upper control arms as mine were off centered and they were only about $50 a side.  If you haven't already, do the Shelby 1" drop, I'm currently in the process of doing this and then will be ordering new coil springs and Maier Racing leaf springs as my car has quite a bit of wheel hop to it.  I wouldn't recommend the opentracker products as they seem to be a bit high and most are Moog or Scott Drake, which you can get at Jegs or summit for much cheaper and then modify them yourself to make them stronger and more durable.  I'd also recommend rebuilding your uppers on your own if you have some knowledge and the ability to as it would save money and would probably have better control arms themselves, especially if they're the originals, in terms of metal thickness and what have you. 

I'd go with...
Moog UCA rebuild kit - $25 per side, Moog ball joints - $25 per side and all made in USA
Moog LCA's - $80/pair
Shelby 1" drop - $30 for drill bit and template
1" lowered coil springs - $75 - $150
Bilstein shocks - $400
Scott Drake urethane perches - $100/pair

With those you are getting all quality parts and not breaking the bank while doing so but aren't getting cheap parts like kyb shocks.  The shocks alone have made a world of difference on my fastback, feels like you're driving a new car, well except for the 450hp 351w in it

barnett468 wrote:

drake makes free moving urethane perches for less than than rollers.

 

Free moving in the hand doesn't equate to binding/drag when loaded with 1000lbs. 

John