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New front suspension....Ugh.... Now I have a 4x4 now

9K views 86 replies 19 participants last post by  69Mach390 
#1 · (Edited)
Car Specs --> 69 Mustang Convertible, 302 w/ c4 auto, w/ A/C;

Tires --> 15" BF Radial T/A's P205/60s

Details of new Suspension Parts:
* UCAs --> Moog RK621369
* LCAs --> Moog RK8123
* Camber / Caster Bolt Kit --> Moog K8293A
* Strut Rod Bushings --> Moog K8157
* Coil Springs --> Moog 8234
* Spring Pearch --> Goodmark GMK30209726435
* Sway Bar bushings --> K90394
* Sway Bar end links --> K700531
* Shocks --> KYB KG4517

Alignment Specs:
* Camber = .25 degree negative
* Caster = 2.25 degree positive on drivers side & 2.5 degree positive on passenger
* Toe = 1/16" per side; 1/8" total

The good news is I no longer have creaky, spongy, sloppy suspension. The bad news is this thing rides like a tank with no suspension movement at all and it looks like a 4x4 in the front. I hate it.

There is literally 5.5" of space between the top of the tire and the fender lip.... :shrug:

Looking at the Moog spring specs for the ones I have, they have a load weight of 1668 lbs and a spring rate of 283 lbs. per inch. This seems like a lot for a light 302 in the front end of this 69. On top of that these KYB springs I have are super stiff. I think my height issue is a combination of overly stiff springs and shocks.

I'm not sure what to do. I have a new set of cheap monroe shocks I'm thinking about throwing in to see if reducing the shock stiffness helps the ride height some as well as the spring stiffness but I'm not too hopeful about that.

I'm not sure I want to cut the springs because that only stiffens the ride although it would drop the ride height.

Anyone know the "stock" spring specs for a 69.... I have the shop manual but I haven't found it yet? Are my new Moog springs way over the spec?

Any other ideas?

This thing is so stiff that normally when you jack up a car there is a good 3-4" of the suspension relaxing (maybe more) before the front tire lifts off the ground but with this thing it's like one pump of the jack and the front tires are off the ground.

The other thing I've noticed is the shocks are not centered in the spring. It looks as though the spring is not centered (too much towards the front) although its sitting centered in the shock tower and spring perch.

Let me know please.... no way this thing will ever settle to a normal ride height with as stiff and high as it currently is.
 
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#2 ·
I don't like the KYB. I had them for about 100 miles before I replaced them with cheap Monroes. With the KYB the car was just too stiff and harsh for my taste. When you tightened the lower control arm bolts, was the suspension fully extended? They need to tightened with the car sitting. I realize on your car you have to adjust the eccentrics for camber, I would think the car was sitting when you did that. Once you get the ride height corrected you will have to definitely reset tow. The wheels like to tow out when extended and tow in under compression.
 
#4 ·
Yes, as Tom said, tighten all components with car on the ground on the tires: Lower A arms, strut rods, & sway bar. If you already did it this way, and you are still sky high...then that is a little strange. I cannot speak for those specific Moog springs, I have only used the Moog 8534 which is a BB spring. I had to buy them when the "new" small block springs I had were too low. I used the 8534's on my 70 coupe with 302, power steering and A/C. With the drop, and new SD uppers and lowers, OT perches, and KYB EXcel shocks the ride height was perfect. I have about an inch above the tire. I have tried 2 different tires on the car...I have the 245/45/17's Mach 1 rims, and also 215/70/14?(I think) on aluminum kidney-bean slots. Both tires are nearly identical in height...maybe 1/4" difference.
As far as firmness, I have very little seat time with this new set up...still stalled in the alignment stage, and then got other projects in front of it.
 
#7 ·
The spring you mentioned is the "go to" piece for performance use at GW.
It is chopped a couple of inches for it to arrive at its 540#/in rating.
I've used it before straight out of the box too. It is a higher rate even out
of the box than the OP's because the wire diameter is significantly
larger. I will agree that it is a nice part.
The OP has the issue of 1/2" excessive height due to gas shocks but
most of his excessive height is elsewhere, if those truly are Moog
8234's on the car. It could be due to everything being tightened while
the car is in the air. I'd rule that out before anything else is done
8234's are pretty soft and the free length seems about right without
chopping for a stock ride height scenario.

ex-Global West GM
1991-1995
 
#5 · (Edited by Moderator)
Everyone says that shocks alone don't effect the ride height. To me just changing out the shocks made about 1/4-1/2" difference. But that's not going to fix your issue. Yes, pictures will definitely help. Also, It might just be me but the picture of those springs on Summit and other sites make them look like they're about twice the length of the standard or 1" lowering springs. I'd get something a bit more performance oriented like a Maier racing, Global West or similar set of quality lowering springs. I myself bought Maier racing 600lb 1" lowering coil springs for my 65 fastback and even those had to have a half coil cut off as you can imagine the original springs had sagged quite a bit over 50 years. If you're looking for a better ride quality get rid of the garbage KYB shocks and get a quality shock like a Koni or Bilstein and some roller spring perches from opentracker. I have both and it makes the ride quality much better as well as the performance compared to the original coil/leaf springs that I could bend by hand when I took them out of the car and the KYB gas a joke shocks that I had on the car to begin with made the thing ride like a dump truck when going over bumps or divots or potholes. Also, did you do the Shelby UCA drop? Not sure if it's a necessity on the 1969 like it is on previous years but that helps a lot as well. Check these out. I know suspension pieces are on the spendy side but they really make a difference. I'd get the roller spring perches and Bilstein shocks shown below and either the Maier racing coil springs below or Global West. Maier racing also has the Bilsteins, I got mine through them and got the sport valved series.

http://opentrackerracing.com/product/roller-spring-perches/

http://opentrackerracing.com/product/bilstein-front-shocks-street-valve-1967-1970/

http://www.maierracing.com/product/mustang-coil-springs/

https://m.summitracing.com/parts/gls-s-26
 
#20 ·
Throw on a set of 18" wheels and problem solved !

I may have missed it , did you loosen the upper arms shaft and retighten ?
 
#22 ·
I'd leave the upper arms alone.
Did you tighten the lower arms with the car in the air? (That's
pretty direct question, rather that "tighten everything in the air)

That spring is more of a "universal fit" like several of the Moog
springs can be considered. It shouldn't take much of a trim
to set final ride height after its settled. Your springs would
appear too long for that wire diameter maybe. Did you compare
wire diameter with the old springs?

You can sometimes adjust that much height difference by
chopping an aftermarket spring without massively affecting
the spring rate but I doubt that's going to happen in this case.

ex-Global West GM
1991-1995
 
#25 ·
The fix for the ride quality and the height are related but are separate fixes.

For one thing, sounds like you'll be happy with a softer shock.

To get lower you're going to either need different springs or to cut the ones you've got. But BOTH of those things will make the ride stiffer.

And "while youre in there" do the Shelby drop. It'll drop you another 1/2" and you'll handle better.

With 1" lowering springs and the Shelby drop, I'm VERY happy with the ride and ride height.
 
#26 ·
".....To get lower you're going to either need different springs or to cut the ones you've got. But BOTH of those things will make the ride stiffer.

And "while youre in there" do the Shelby drop. It'll drop you another 1/2" and you'll handle better. ....."
Affirmative on the Shelby drop.

However, If the OP puts on different springs (that have a softer rating) how will that make the ride stiffer ?

Z
 
#27 ·
Softer rate of same length will lower car and not make it stiffer.
 
#32 ·
Well, since trusting my memory wouldn't be wise, we can look at any of the ads for these cars from 1964-'70 and there is no ad that has the car sitting up where the OP's car is sitting, not even close. I don't know if the springs sold today are the exact same spec. spring as came on the car when new, but as far as ride height goes, there is a recent thread here that discusses that in detail. A Ford TSB was issued in '66 that gives the factory take on ride heigh and its in the thread.

Z
 
#42 ·
True but keep in mind that the OP is using considerably shorter tires than it rolled off the line with,insuch not filling out the wheel well
Since I have to remove the springs regardless (whether I cut them or replace them) I decided I'm going to do the Arning drop as well today. I figure I'll do the drop, then re-install the uncut Moog spring and if the height is still too high I will decide from there if I cut them or order some other manufacturer of the coil spring.
UCA drop will only gain you (or lose you depending how you look at it.Glass half full or half empty) 5/8-1/2"ish
 
#33 ·
Well no, they probably didn't come from the factory at this ride height but the Moog coil springs are also probably a thicker gauge wire than the originals. I'm thinking the 16" springs with possible a thicker gauge coil would be the culprit. I also know that some manufacturers make their coil springs long so that you can cut them to your own length to where you want the wheel height. The Maier racing springs that I got were this way as they didn't want to make the springs too short and have people with the car sitting too low and have to ship multiple sets of springs back and forth. It makes sense to me as you can always cut more off but can't add extra material to springs that are cut too short.
 
#35 ·
Since I have to remove the springs regardless (whether I cut them or replace them) I decided I'm going to do the Arning drop as well today. I figure I'll do the drop, then re-install the uncut Moog spring and if the height is still too high I will decide from there if I cut them or order some other manufacturer of the coil spring.
 
#38 ·
After you dropped the car onto the ground, did you roll it around and out of the garage? The front end will drop down quited a bit once the suspension is cycled through it's movement. I have a long bumpy driveway that I like to go up and down a few times to get things where they should be. Just a thought. and yes, do the drop, that will get you another 1/2 inch lower.
 
#41 · (Edited)
I have had changes of 3 inches or more from cycling suspension after it was sky high, I had 3 inches clearance above tire, went up the driveway, bumps and all, and returned to have the top of tire tucked inside the fender well. Almost too low in my opinion. Still debating If I want to pull the small block springs and install a MOOG BB spring.

I have also experienced "new" stock spring perches that were defective out of the box, and would not allow the front end to come down due to binding. I got free upper A arms from this, because owner purchased new parts and gave me the the pull-offs. It was the defective perches that made the car sky high, with major camber. Once new perches, coils and A arms were installed, the car sat back down where it belonged. My Friend was sold on the roller perches after banging his head so much with the new factory parts.
 
#44 ·
Your right...I missed that on the tank like ride. And as stated earlier, the tire size is also a consideration. I sometimes gloss over the basics and then wonder "What the HE** did I do?
 
#45 ·
No worries all... thanks for all the options / opinions. Today is a what i call a "free-day" meaning no obligations like honey-do lists or kid's activities or family events going on so I'm going to spend the rest of the day playing on the car and see where I end up.

I'll let you know.
 
#47 ·
stolen from tire rack
For example: The 1965 Ford Mustang's 6.95-14 would be replaced with a P185/75R14.

Tire Size Overall Diameter Section Width Load Capacity
6.95-14 25.3" 7.0" 1230 lbs @ 32 psi
P185/75R14 25.0" 7.2" 1290 lbs @ 35 psi
I guess considerably wasn't exactly the right word to use ,but still different
Also Didn't mean to imply that was the only issue the OP was having
 
#48 ·
Yeah, since the OP is using 15" wheels, there isn't much difference in overall tire diameter from the stock set up, even though he has 60 series tires.

The springs themselves are most of the issue here , imo. Sadly, there are many manufacturers that say their product is a direct factory replacement, when it is not that at all.

Here is a tire size calc that is my favorite:

http://www.powerdog.com/tiresize.cgi

Z
 
#51 ·
Success!! One word.... Yeeha!

After the shelby drop I also ended up removing 1/2 a coil and now she sits ~2" from the top of tire to the fender lip which I am thrilled with. That height is also consistent with the rear wheel as well so the over all height now is pretty nice. I'll post pics once I get done with the alignment.

Now that I did the shelby drop, what should I be using for my camber and caster settings on the driver and passenger side? Toe-in I'll stick with the 1/8" total, maybe closer to the 1/16".
 
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