unstable suspension

[Dave0803]

I have a 2003 GT with max speed springs-2" drop (yes I know they are crap), bumpsteer kit, and BBK C/C plates. Other that what I have listed, everything else on the chassis is stock. My problem is when I am driving on anything other than a flat smooth road the car wants to wander in every direction. What advice or suspension set up could help with this issue. I want to use it mostly as a daily driver and drag strip car. I was thinking of the ford B springs. I am also running the stock sized tires (245/45R17).

 

[squares98]

http://www.miracerros.com/mustang/t_suspension.htm

 

[sgarlic]

My advice is to get an alignment if you haven't done so already.. that should help the wandering.

 

[tomustang]

bumpsteer

 

[stangliter04]

shocks and struts/ if you are still running stock im sure they are shot.

 

[Kilgore Trout]

Get special ball joints for lowered cars or drop spindles. Also get offset steering rack bushings.

 

[hognutz]

Well first off do some reading. read that link above and go to maximum motorsports website they have some good reading. there is quite a bit of confusion over bumpsteer and how to fix it. I would not recomend offset rack bushings if you already have a bump steer kit. I don't have offseet bushings or bump steer kit and I don't really have noticable bump steer. my alinement is correct though.

1. Is the alinement good?
2. is the bump steer kit installed correctly?

there are four things that will cause a car to drive crappy.

1. alinement
2. bump steer
3. tramlining (following groves in the pavement)
4. worn out parts. (baljoints, bushings, etc)

tramlining is ussually going to happen a bit with high performance tires. If you car is wandering at any other time it is most likely bump steer or alinement.

I would personally go with a differnt spring and ditch the bump steer kit. I have a feeling the kit could just be installed wrong. they are not the most simple installation if you read the instructions. as long as the tie rod is at the same angle as the a arm you should not have much bump steer. you should be able to just look and see if this is correct.

I like the H&R springs. sport are 1.6,1.5 drop with like 490-570 rate up front. supersport are 1.75,1.6 drop with 700-750 up front. both are like 250-280 in the rear.

the ford springs are cheaper but only drop .75 in the rear. the b springs are pogressive and c spring is fixed 650 up front.

once you start undestanding what the mods do it is easier to find the problem. for example the x2 baljoints fix roll center issues with a lowered car but they take the a-arm and tie rods out of alinement and this is when you usually need a bump steer kit. this is something I would not mess with. I would just only lower the car 1" and run race springs. cheaper and don't have to mess with the install. offset rack bushing can change the relation of the a-arm to tie rod if nessesary but that is not always needed like some people think. they can also cause interference with some headers. so just read and search all the info is on here already.

 

[Dave0803]

Since the last post I have taken the suspension back to stock till I can get the parts I want but the car actually feels worse now than it did before. Eevn just changing lanes because of the crown in the road causes the steering to become irratic. Going even over the slightest imperfection in the road where the suspension is not compressed evenly causes the car to become unstable. I had it alingned and checked over after I did the work.

 

[tomustang]

Since the last post I have taken the suspension back to stock till I can get the parts I want but the car actually feels worse now than it did before. Eevn just changing lanes because of the crown in the road causes the steering to become irratic. Going even over the slightest imperfection in the road where the suspension is not compressed evenly causes the car to become unstable. I had it alingned and checked over after I did the work.

shocks/struts

 

[tomustang]

wow, I'm blunt

 

[Mel96GT]

If you are lowering for looks, you will spend mucho money for that 2" drop. It will also kill your 1/4 mile ET's. Your car will not handle any better, than a properly tuned 1" drop suspension. My advice would be to get a 3/4" Bullit suspension kit that way you won't change the geometry of the car's front suspension/steering. In my experience the SN97 suspension seems to be very sensitive to changes so you should stick to proven factory mods (which is what I did) unless you want to spend a lot of money.

I know others have spent big bucks on their trick suspensions but I'm not ready to do that. I am perfectly happy with my slightly modded suspension. I also strongly recommend SFC's.

FWIW, the full-race springs are about 1" drop, maximum.

 

[tomustang]

If you are lowering for looks, you will spend mucho money for that 2" drop. It will also kill your 1/4 mile ET's. Your car will not handle any better, than a properly tuned 1" drop suspension. My advice would be to get a 3/4" Bullit suspension kit that way you won't change the geometry of the car's front suspension/steering. In my experience the SN97 suspension seems to be very sensitive to changes so you should stick to proven factory mods (which is what I did) unless you want to spend a lot of money.

I know others have spent big bucks on their trick suspensions but I'm not ready to do that. I am perfectly happy with my slightly modded suspension. I also strongly recommend SFC's.

FWIW, the full-race springs are about 1" drop, maximum.

But see he reverted back to stock, when he had the max sp'e'd springs in he blew out the dampers, now he needs replacments.

Why couldn't you just keep my answer to being blunt like I wanted it to be?