suspension question.. bodyroll?

[kubusio]

i have a 02 gt with an IRS from a 99cobra. here is what I have done to the suspension..

Shocks and struts form 04cobra
Eibach sportline springs in the front
H&R race springs in the rear--IRS

the front of the car is really stiff but it seams as the rear is a bit soft because when I take turns it seams as the rear sits alot and the front doesnt. Like the fornt and rear dont work together.

Could it be the sway bar in the IRS?
what else could it be? cause I thought that the H&r are stiff springs.

 

[MidLifeC]

A couple of things can contribue to this. You have mixed spring brands, not a good thing. They are sold in sets for a reason. You haven't upgraded the dampers - HR race are close to Cobra R rates? Then you need Cobra R dampers. Did you disassemble the IRS? Have you retorqued the control arms at ride height? The last thing - all the rubber in the stock IRS system will contribute to body roll. Have you replaced any of it? Have you done any body stiffening? SFC's or IRS cantilever brackets?

 

[kubusio]

The IRS is stock and I never took it apart. I changed the bushings that attach the Irs to the car. Also, 04 cobra shocks and H&R race springs.
so the shocks of an 04 cobra arent good for the H&R race springs?
The reason I have to mix the springs because if I put H&R's race in the front it will be way too stiff cause my nose isnt as heavy as a cobra.

 

[MidLifeC]

I believe the shocks are marginal - someone with more experience can answer. Are you trying to say the rear will move around during hard cornering? If so that would be the soft rubber bushings in the IRS. Ask / search in the '99-'01 Cobra forums to see what their experience is.

Other factors can contribute, can you describe your problem better?

 

[kubusio]

The IRS feels in place when I take a hard turn but it feels like the rear compresses down alot and the front doesnt. It feels like body rool but only in the rear.
I do have sub conectors so I know its not the chassi flexing.

Also when I push down on the rear of the car it feels really soft. and the front is stiff as hell.

 

[CobraRed01]

What color are your H&R springs...red or blue?

 

[kubusio]

What color are your H&R springs...red or blue?

RED. race springs

 

[CobraRed01]

Good...some have reported ending up with the wrong H&R springs (blue Sports) in the past and didn't realize it. You said you changed the IRS sub-frame bushings...did you go to poly?... or just new rubber? Also, IRS sub-frame bolts from Ford were not right size. If you don't have them check Maximum Motorsports for poly kit and get the right size bolts from them as well. That could help. Also, Max Motorsports techs are real helpful if you have a Q regarding Bilsteins, etc. Ask for Matt.

 

[racebronco2]

[/IMG] here is a picture of my car and you can see it does have some bodyroll.the shocks are ok with the h&r's but any stiffer and they cannot control the springs. i checked out my car and when i push down the front feels stiff and the rear is softer even though i have stiffer springs in the rear. my car does lean in the turns with stock 29mm front and rear swaybars, 750-800 fronts and 800-850 rears springs.

 

[99COBRA2881]

The reason I have to mix the springs because if I put H&R's race in the front it will be way too stiff cause my nose isnt as heavy as a cobra.

Who ever told you that is full of crap, the iron block aluminum head GT motor weighs in at 610 lbs. The Aluminum block and heads DOHC motor weighs in at 550 lbs. If you're still worried about weight differences, relocate the battery to the trunk and you'll be close to the same weight distribution as a 99-01 cobra.

Also these cars will not corner flatly. They will have some body roll and thats actually a good thing. If you make the front end too stiff, you'll have a corner plowing understeering pig. The race springs are a very good setup with the Bilstein HDs.

 

[racebronco2]

i agree with 99cobra2881. they were probably talking about the 03/04 cobra.

 

[pipeliner]

Bigger bar or more front spring. Either way the ride quality is going to go in the crapper.

Im currently around 1400 pound springs in the front and can still cause the car to obtain some insane body roll.

 

[kubusio]

thanks for all the replys. I am going autocrossing tomorrow and Ill see how it feels.

Does anyone know if the specs on h&r front race spring and eibach sportline front spring? Which one is stiffer and by how much?

 

[racebronco2]

the h&r race springs are stiffer then the eibach sports or pro's. that is why i am running h&r front and eibach pro's in the rear. the rear pro's are stiffer then the h&r's race.

 

[kubusio]

the h&r race springs are stiffer then the eibach sports or pro's. that is why i am running h&r front and eibach pro's in the rear. the rear pro's are stiffer then the h&r's race.

I didnt know that the pros are stiffer. I might need to switch

 

[99COBRA2881]

kubusio-- How many times have you been on track before???

 

[kubusio]

kubusio-- How many times have you been on track before???

Never road raced but about 10 autocrossed. I know I dont have much experience on an open track but I feel my car on the street when I take sharp turns.

 

[blaire576]

i have a 02 gt with an IRS from a 99cobra. here is what I have done to the suspension..

Shocks and struts form 04cobra
Eibach sportline springs in the front
H&R race springs in the rear--IRS

the front of the car is really stiff but it seams as the rear is a bit soft because when I take turns it seams as the rear sits alot and the front doesnt. Like the fornt and rear dont work together.

Could it be the sway bar in the IRS?
what else could it be? cause I thought that the H&r are stiff springs.

hope you'll have a good race./ :rockon:

 

[99COBRA2881]

I just think you're worrying too much about the car that's all and before making a bunch of changes you need to get on track first.

 

[Cobra-R]

I just think you're worrying too much about the car that's all and before making a bunch of changes you need to get on track first.

I agree. Get on some big tracks, you will be tracking for a couple years minimum before you can use your exhisting car setup to it's limit. Learning is the fun part. :beer:

Brian