Bottoming Out!! HELP!!!

[cobrakid14]

So I have an MK2 with the stock mustang rear end, quad shocks, and cut coil springs. The springs are adjusted all the way up in the rear and on sweeping bumps I hear my rear tires scrubbing the body. Any suggestions on how to remedy my problem? Thanks!

Jason

[Pedalmasher]

Prob first you need to figure out where on the tire it's rubbing. If you're rubbing the outer sidewall, is the body moving sideways over the frame? You may need a Panhard rod to hold it aligned.

What is the condition of your suspension arm bushings? Rubber, or poly? A new set of poly bushings will do wonders - again, by helping to hold everything more in alignment.

HTH,

Derrick

[Hunter 2]

I had the same issue with 2329 until I removed the limiting straps. Do you have limiting straps?

[Dan Babb]

Maybe the springs are sagging and just not up to the task any longer. I had that issue on my first FFR and put in a set of spring spacers and it helped. The ones I had were these funky shaped steel pieces that slid in between the upper coils of the spring. Something like this might be more effective.

Superior 18-1201 Spring-Lox,2-Way Adjustable Spring Spacer : Amazon.com : Automotive

Superior 18-1201 Spring-Lox,2-Way Adjustable Spring Spacer : Amazon.com : Automotive

But I eventually changed the rear shocks to coil overs to get better adjustability and handling. Well worth keeping an eye on the classified section for a good set of used coil-overs.

[cobrakid14]

Derrick- I made a set of lower control arms at my buddys fab shop last week and I will be making the uppers next weekend. They have poly bushings in the arms as well.
Do you have a picture of a panhard bar installed on a FFR?

Hunter- I do still have the limiting straps on my car!

Dan- I will keep my eyes open, but i was hoping there was something I could do sooner!

[Gregg Wade]

Are you sure it is tires rubbing? It could be drive shaft bind try shimming the tail shaft up a 1/2" and se if it gets any better.
Gregg

[Seagull81]

If there is any way you can afford coilover shocks, do it. That was the best upgrade I have done on the car. It gave the car much easier adjustability and more control as you drive.

[steno]

Just get control arms from summit.New,powder coated, and there in 2 days. That was my choice and never looked back!

[cobrakid14]

Gregg- I am sure its the outside edge of the tires rubbing on the body.

seagull- Any reccomendations on coil overs? Thanks

Steno- I work part time for a company that supplies Massivespeedsystems.com all of their parts, so I made an extra set for my car!

[Scott Shumaker]

I would suggest using rubber bushings in the upper arms of the four link. They will help to eliminate the roll-bind that is inherent with the stock four link suspension of the mustang. Also, what is your rear tire size, and offset of the wheels? Need more information before I can give an educated answer.

Just a thought.

Scott

[cobrakid14]

The set of upper control arms i will be using has poly bushings in them. my rear tire size is 275 40 zr17 and they on the 4 lug hilibrand wheels from factory five. I think the rears are 17x 10.5

[rokfor]

I had the same problem on my MKII until I switched to the coilovers that VPM sells. It made a HUGE difference.

Rob

[DAVE LITHWAY]

X-2 on the coil overs. I changed out the stock donor system on my Mark I to coil overs and FFR lower control arms. 250 pound springs, and 4-7/8 inch ride height in the rear. My tire size is 295 -50 X 15 and the rubbing on bumps has gone away except on the most violent dips. Going to coil overs (nearly any brand) and spring rates in the 250 to 300 pound range will really improve your ride and allow easy height adjustment to accomodate your tire size.

Dave

[CraigS]

Had the same problem on my MkI. The builder had cut off part of the spring per FFRs instructions. My first solution was to get another pair of springs. I then used a torch to heat the spring ends and opened up the end where it closes down. this way I had more spring engagement on the spiral thingy and could adjust it high enough. Of course a while later w/ a little more $ accumulated, i got coilovers.

[tomh440]

Like other say, upgrade to coilovers. I had the stock mustang stuff and bottomed out and driveshaft bind. I upgraded to Bilsteins and am very happy. I'm sure Koni's or VPM, Breeze QA1's are all fine upgrades and will make a huge difference.
Just do it now and you will always be very happy you did.

[steno]

Originally Posted by tomh440

Like other say, upgrade to coilovers. I had the stock mustang stuff and bottomed out and driveshaft bind. I upgraded to Bilsteins and am very happy. I'm sure Koni's or VPM, Breeze QA1's are all fine upgrades and will make a huge difference.
Just do it now and you will always be very happy you did.

Same thing for me...went with the VPM setup... never an issue again!

[PGCobra]

Stock Mustang springs are variable rate and in the FFR they run on the soft end which is around 125lb/in. Change to a set from a Bullit or a Mach1 which are 250lb/in linear and you will get a massive improvement. Or go the coilover route suggested

[cobrakid14]

pgcobra - any year mach 1 spring? I figured if i could spend a few bucks on new springs , it would do for the rest of the season. then over the winter i could upgrade if funds are there...

[PGCobra]

Bullitt 2002
Mach 1 2003, 2004

I picked up a set of Bullitt springs on a Mustang forum in their classifieds