Welcome to Track Mustangs Online

Join the BEST track enthusiast Mustang community on the web!

Register Log in

I want to lift my S197 GT350 a little bit

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
Guys,

I love my widebody convertible, but there is a specific issue with the rear suspension. Both rear tires rub on the fiberglass quarters over medium to big bumps in the road. It's not a centering issue since they both rub about the same haha. I was wondering if some adjustable coil overs would be the best course of action. The wheels and tires are 20x13 with 345's. The wheels are very rare and specific to the widebody cars so I don't want to change them out.

Any suggestions? Frankly I wouldn't worry about it, but I can smell the rubber every time since it's a convertible and it annoys me. Better handling would be great bonus. I think it's got some sort of Ford Racing shocks and struts from the build at Shelby American.

CSM 133500068. Does this widebody make my butt look fat? :oops:

 

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
I guess that's an option. With the s/c Coyote she's got a lot of power and can use all the traction she can get.
 

racer47

All I got left is fast
Messages
224
Reaction score
243
Location
SE WI
The cheapest / easiest way is stiffer rear springs. 12" x 2.5" coil over springs fit in place of stock springs. You would need something like a 185 lb to 200 spring rate. But this will be non-height adjustable.

There are adjustable rear spring perches like this that will give ride height adjustability https://www.maximummotorsports.com/Mustang-Rear-Ride-Height-Adjusters-with-helper-springs-2005-2014-P1483.aspx

You probably don't have room for a true coil over because of the tire size and limited clearance between the tire and shock.

But whatever you do, going to a smaller tire and / or wheel is just not an option :)
 

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
Thanks racer47. I've never seen those before. I'm not sure I want to go this high though:

"For any particular spring, the minimum adjustment setting will raise the rear height by 1.85", compared to the same spring installed without this adjuster."

Good point about clearance for coil overs. I'll hit up the boys on Team Shelby and see what the optional suspension was for my car.
 

racer47

All I got left is fast
Messages
224
Reaction score
243
Location
SE WI
Last edited:

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
You don't raise the car by 1.85". You use the adjustable perches with 8" or 9" or 10" tall 2.5" dia coil over springs. The spring height you need depends on the spring rate you want.

So you need to buy perches and springs. Here is an example calculation for the spring height that you need.

https://trackmustangsonline.com/threads/where-can-i-buy-sell-trade-coilover-springs.13428/#post-196183

What springs do you have now?
Thanks. So If I went this route, I'd buy a spring set that matches for what I would want to do? I have no idea what springs are "stock" on the car, but I have that question posed in my thread on Team Shelby.

CorteX Cambered Rear Axle, duh.
LOL, If I were caging the car and making a racer I might.
 

racer47

All I got left is fast
Messages
224
Reaction score
243
Location
SE WI
So If I went this route, I'd buy a spring set that matches for what I would want to do?
Yes

If your springs are Ford stock, they will be about 150 lb/in. If you want a near stock ride at near stock ride height, then 175 or 185 lb/in, 10" tall, 2.5" dia springs and the adjustable perches, should be about right. If you need extra ride height, then maybe 11" springs are needed.

The stiffer the spring, the less ride height you will need to stop the rubbing. When you get up near 200 lbs and higher, the ride difference will be noticeable. 250 will be very noticeably stiff.

175 lb/in or 185 lb/in is what I would consider stockish ride. The stock GT rear springs are too soft. So a little rate increase is better. If you knew your current spring rate and free spring height, I could give a more exact answer.

But, in reality, coil over springs are relatively cheap. I'd just buy the perches, take my best guess at a spring and give it a try. If its not exactly right, buy a different pair of springs.
 

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
Yes

If your springs are Ford stock, they will be about 150 lb/in. If you want a near stock ride at near stock ride height, then 175 or 185 lb/in, 10" tall, 2.5" dia springs and the adjustable perches, should be about right. If you need extra ride height, then maybe 11" springs are needed.

The stiffer the spring, the less ride height you will need to stop the rubbing. When you get up near 200 lbs and higher, the ride difference will be noticeable. 250 will be very noticeably stiff.

175 lb/in or 185 lb/in is what I would consider stockish ride. The stock GT rear springs are too soft. So a little rate increase is better. If you knew your current spring rate and free spring height, I could give a more exact answer.

But, in reality, coil over springs are relatively cheap. I'd just buy the perches, take my best guess at a spring and give it a try. If its not exactly right, buy a different pair of springs.
Thanks for the advice. I've got an email in to Shelby American asking what exact springs came on the car. I'll update when I find out.

What kind of tire?
Pilot Super Sports.
 

Competition Orange

TMO Advanced
Messages
131
Reaction score
75
Location
Columbus, Ohio
You're trying to compensate for a lack of grip from the mpss with width. If you get some better tires (more sticky) you'll have even more grip, proper fit, no rubbing, and best if all better performance.
 

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
Well technically I'm not trying to compensate for anything other than the rubbing since the tires are bone stock for the car. That is a decent idea to go with a narrower tire though. Sounds like whatever I do it's gonna cost me.
 

Fat Boss

TMO Addict
Messages
1,303
Reaction score
216
Oh man you're reminding me of when my dad made wooden, yes wooden motor mounts for his 71 F250 when he swapped out the 360 for a 400...
 

racer47

All I got left is fast
Messages
224
Reaction score
243
Location
SE WI
They can be steel or aluminum if you want but then you are taking a chance of making noise. Wood is quiet and will work well. You can also shim between the spring and axle but that would need to be metal because there is less surface area to work with and it will get wet in the rain.
 

TMO Supporting Vendors

Latest posts

Top