Ford Mustang Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
383 Posts
Discussion Starter #1
I recently had a TA and PHB installed on my car. The lowest point on my car is alot lower because of these two items. I noticed that when i have more than one person in my car and i hit a slight bump, the bottom of my car hits the pavement and scrapes. Would stiffer springs fix this? I am currently running eibach progressive rate springs, but am unsure of the lbs.
 

·
Super Moderator
Joined
·
27,657 Posts
But a TA and PHB move with the suspension, not the body. The only real point of compression between them and the ground is the tires. Are you sure it's one of those items hitting the ground? Are you sure it's the ground they're hitting?
 

·
Registered
Joined
·
383 Posts
Discussion Starter #3
MFE,
Well when i hit a big groove in the ground and i have more than one person, i feel the car lightly scrape the bottom. Also, when I take sharp left turns (like in autox) i hear the wheels rubbing. Now that i think of it, could it be my body rubbing against the wheel when i hit these grooves? That would make sense, but why would that happen after i installed the PHB and TA?
 

·
Registered
Joined
·
230 Posts
Possibly the PHB installation does not have the diff centered in the chassis. That can be adjusted out. Sounds like you need to do some looking and confirm what you think are hearing:
1. take the rear wheels off and look in the rear wheel wells
2. Put fat friends in the car and see what is the lowest point other than what is directly below the wheels.

I gather that you did not do the install yourself so worse come to worse take it back and whine :)
 

·
Registered
Joined
·
5,911 Posts
Aren't you supposed to run stiffer rear springs with a torque arm?
 

·
Registered
Joined
·
364 Posts
Oktavius said:
Aren't you supposed to run stiffer rear springs with a torque arm?
Yes it does.
 

·
Registered
Joined
·
3,627 Posts
blown5.0 said:
I recently had a TA and PHB installed on my car. The lowest point on my car is alot lower because of these two items. I noticed that when i have more than one person in my car and i hit a slight bump, the bottom of my car hits the pavement and scrapes. Would stiffer springs fix this? I am currently running eibach progressive rate springs, but am unsure of the lbs.
Installing a TA in place of the stock quadra-bind setup will require much stiffer rear springs to prevent excessive body roll. How much stiffer will depend on the front spring rate or better yet the wheel rate. You want to maintain a certain balance between the front and rear springs.

FWIW if your running Eibach Proline springs they are too soft for even a quadra-bind setup to work properly. I would recommend reading THIS and then choosing a more appropriate spring.
 

·
Registered
Joined
·
383 Posts
Discussion Starter #8
Thanks alot for the info. I went to my suspension guy today and he told me that the addition of the TA and PHB took away approximately 50 lbs from the springs in the back so I need to get stiffer springs as you guys mentioned. It is body roll I am experiencing as my tire is rubbing the fender well in the back. Now I only have one problem. How do I know what spring rate I currently have? Is there a part number I can look up?
 

·
Registered
Joined
·
700 Posts
The rear springs are shorter than stock, and only 200-250#. (stock are 200-300#).

The fronts are slightly heavier than stock... 470-570 or so.

Get a proper set from Maximum motorsports.
 
1 - 9 of 9 Posts
Top