Rear suspension setup. Whats my best alternative here?

[281pony]

i just did my 5-lug conversion. i have some very very tight tolerances on the rear, im in a dilema. the stance is great height wise. the wheels articulate fine into the wells. however, when i get side to side axle movement, they are touching.

i have adjustable LCA's. not sure who makes em, it just has the adjustable pedestal's using a 1/2" extension. ok great, well the one bolt is sheared/broken off we discovered today. i got the car like this. we unloaded all the weight off it, and compressed the spring to move it. it is seized into the control arm.

so here is what is going through my mind.

1) get coil overs. i have qa1 shocks. get the brackets/springs/retainers and i should be good to go. pull out my springs/perches from the arms

2) get new adjustable LCA's and adjust accordingly for ride height.

3) get a panhard bar setup. this is my last option i think. i have tails and real tight clearances as it is. this seems like the most complicated setup, although maybe the most rewarding?

the car is 97% street, it might see the track some. next thing for me will be power mods, 400 rwhp range. i dont autocross, i dont do any aggressive handling essentially, to make use of the panhard fully. i just need to be able to drve the streets without cutting my tire up.

what do you guys think?

 

[NIKwoaC]

It's actually the job of the upper rear control arms to keep side-to-side movement to a minimum. If you still have the flimsy stock UCAs, you should start there before you go with a panhard bar.

Of course, you should definitely address the broken bolt issue, too. Haha.

 

[90lxcoupe]

are you ever going to race the car on drag radials or slicks? and do you have any intentions of putting a taller tire on the car? If you can weld you could get wolfes adjustable setup that mounts to the body

 

[281pony]

i might race it rarely. nothing serious though.

never plan to really run a slick/taller tire. since i have sn95 axles, it complicates slick selection/adjusting for the track that much more inconvenient.

i just want simple, go in there and get it done.

my uppers are aftermarket as well btw. not sure what brand.

 

[2000xp8]

Changing the axles to 5 lug length will probably be the cheapest easiest route (if you have enough clearance on the inside).

I bought a panhard bar to put on because of the same issue.
But money adds up quick, with the panhard bar i need either a new dynomax exhaust or to have it custom fixed.

You could always get a watts-link too, but again some of those kits have exhaust issues too.

I also don't think changing the rears is going to do much, most places recommend the ford racing uppers, with are just stiffer stock style units.
Supposidly changing out the uppers to something with urethane causes suspension bind.

 

[thethirdeye88]

call maximum motorsports and talk to jason...he is very knowledgeable and will tell you everything you need to know...

 

[S&B]

I faught with this issue once, i ended up going with adj. UCA's with poly bushings and got the wheels to fit perfect on each side, I have Pro3 industries adj. LCA's that i use for adjusting hieght, and the fenders are rolled. I haven't had the problem since, i did do a a bit of custom BFH modificatoins to a master technitians spec on the the exhause and inner fenders wells for a tad bit more clearance. Seems to be working

 

[281pony]

my issue lies completely in the outer clearance. i have the wheels positioned perfect, its just that tiny bit of side to side play im fighting. i either lock it in place with a panhard, or raise the fender lip (adjustable lca, coil overs).

i drove it 40 miles today and didnt here it scrape at all i guess for now ill leave it.

 

[RichC93]

Changing the axles to 5 lug length will probably be the cheapest easiest route (if you have enough clearance on the inside).

I bought a panhard bar to put on because of the same issue.
But money adds up quick, with the panhard bar i need either a new dynomax exhaust or to have it custom fixed.

You could always get a watts-link too, but again some of those kits have exhaust issues too.

I also don't think changing the rears is going to do much, most places recommend the ford racing uppers, with are just stiffer stock style units.
Supposidly changing out the uppers to something with urethane causes suspension bind.

I've been looking for a tread on the binding topic but no real solutions. I have a 93 notch with a 5lug swap. I installed a full poly bushing suspension kit on it because the old stuff was worn. I followed all the instructions that came with the kit and they said to avoid bind use the specific bushings and to install them a specific way to avoid the "bind". I dont feel a bind or stiffness but what I do feel is a lazy muted rear. The front is solid and responsive but the rear is muted and offers no feedback. It has stock arms, constant rate ford performance springs (all 4 corners), KYB performance shocks. I've raced karts for 10 years and know how to setup a kart chassis but the rear of that stang has me baffled. I've been thinking of putting all new stock bushings in it to see if the poly stuff is the issue but I want the rear to feel solid and give me feedback and dont know if that is the right way to go.....

 

[2000xp8]

The rear is pretty simple, each time you fix one problem, the issues move elsewhere until you ultimately fix them all.
So you shored up the bushings, but the arms themselves flex.
You could box them in (total waste of time IMO), or just replace them. It will start to get better, but the reality is that a fox rear can move left to right something ridiculous like 2 inches. (the panhard bar, gives the solid feel you might be desiring)
I'd Replace at least the lowers with something high quality (it's a once in a lifetime mod for most people, so I wouldn't let cost dictate what you buy).

Maximum motorsports is pretty much my suspension bible.
Pricey? Yes.
Am I a fanboy? I guess you could say so.
But i've yet to be let down by them as a company ever...

 

[RichC93]

The rear is pretty simple, each time you fix one problem, the issues move elsewhere until you ultimately fix them all.
So you shored up the bushings, but the arms themselves flex.
You could box them in (total waste of time IMO), or just replace them. It will start to get better, but the reality is that a fox rear can move left to right something ridiculous like 2 inches. (the panhard bar, gives the solid feel you might be desiring)
I'd Replace at least the lowers with something high quality (it's a once in a lifetime mod for most people, so I wouldn't let cost dictate what you buy).

Maximum motorsports is pretty much my suspension bible.
Pricey? Yes.
Am I a fanboy? I guess you could say so.
But i've yet to be let down by them as a company ever...

Thank you for the reply and the info. I'll be looking into them.

 

[Warhorse Racing]

I've been looking for a tread on the binding topic but no real solutions. I have a 93 notch with a 5lug swap. I installed a full poly bushing suspension kit on it because the old stuff was worn. I followed all the instructions that came with the kit and they said to avoid bind use the specific bushings and to install them a specific way to avoid the "bind". I dont feel a bind or stiffness but what I do feel is a lazy muted rear. The front is solid and responsive but the rear is muted and offers no feedback. It has stock arms, constant rate ford performance springs (all 4 corners), KYB performance shocks. I've raced karts for 10 years and know how to setup a kart chassis but the rear of that stang has me baffled. I've been thinking of putting all new stock bushings in it to see if the poly stuff is the issue but I want the rear to feel solid and give me feedback and dont know if that is the right way to go.....

There are good poly bushings and bad poly bushings when it comes to the rear end. In the UCA/LCA, you want to use 3-piece poly bushings. Most of the poly bushings made for OEM rear control arms aren't 3-piece bushings. So, you end up with deflection and bind. Especially at the limit of traction.

In order to get the rear end to feel present and consistent while maintaining the OEM design, you have to remove the weak links. Here's a video I made about the rear suspension parts I used on my SRA autocross Mustangs. It's a relatively inexpensive setup when compared to the other available options. The video details the benefits of each specific part.


View: https://www.youtube.com/watch?v=LD0fMKnKEnI&t


If you have any questions, please ask. I'm always happy to help.