understeer q?
06-05-2009, 12:55 AM
#1
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understeer q? Whats the best way to get rid of understeer in my car? right now the car only has eibach pro-kit springs and KYB 8-way shocks plus the slp 1LE sway bar up front
Last edited by Tdawg; 06-05-2009 at 01:02 AM.
06-05-2009, 01:13 AM
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06-05-2009, 02:23 AM
#9
1. Raise the tire pressure in the front and lower it in the rear
2. Adjust the rear shocks to a firmer setting
3. Adjust the front shocks to a softer setting
4. Larger rear sway bar
What's the size sway bar you have up front? It might be too big compared to your rear bar.
2. Adjust the rear shocks to a firmer setting
3. Adjust the front shocks to a softer setting
4. Larger rear sway bar
What's the size sway bar you have up front? It might be too big compared to your rear bar.
06-05-2009, 07:40 AM
#10
I cannot believe the responses that have been posted here to fix understeer. Those are the most ridiculous "fixes" I have ever read.
You car needs ADJUSTING, not more parts thrown at it. SFC, STB or even better tires will NOT change the balance of the car. It will change the balance in your checking account and tires might mask the problem.
But understeer will still be there
The only post with any real data ... although changing the shock settings to help the oversteer will just move the problem to somewhere else.
If the car is understeering, you need to change the effective spring rate to make the front rate more closely match the rear.
You can do that by a laundry list of ways, like the batmobile dood suggests.
Changing air pressures. Do you realize that 1psi hot change in air pressure can move the effective spring rate by as much as 10in/lbs?
Changing rear spring rates is probably the easiest way. Go to places like daymotorsports.com or pitstopusa.com and order a set of rear single pig-tail springs, typically under $50 each, and exchange the rears. I suggest an 11" x 175in/lb spring and use the isolator.
Or, go to a bigger rear bar - smaller front bar. I would probably chose a bigger rear bar as your front spring rate is too soft to begin with.
If you are "feeling" understeer, then it is massive. The only way I can tell if the car is understeering is with a temperature probe and looking at lap times.
It gets to a point where 1/2 psi adjustments in air pressure is what it takes to podium or load and go home.
You car needs ADJUSTING, not more parts thrown at it. SFC, STB or even better tires will NOT change the balance of the car. It will change the balance in your checking account and tires might mask the problem.
But understeer will still be there
1. Raise the tire pressure in the front and lower it in the rear
2. Adjust the rear shocks to a firmer setting
3. Adjust the front shocks to a softer setting
4. Larger rear sway bar
What's the size sway bar you have up front? It might be too big compared to your rear bar.
2. Adjust the rear shocks to a firmer setting
3. Adjust the front shocks to a softer setting
4. Larger rear sway bar
What's the size sway bar you have up front? It might be too big compared to your rear bar.
If the car is understeering, you need to change the effective spring rate to make the front rate more closely match the rear.
You can do that by a laundry list of ways, like the batmobile dood suggests.
Changing air pressures. Do you realize that 1psi hot change in air pressure can move the effective spring rate by as much as 10in/lbs?
Changing rear spring rates is probably the easiest way. Go to places like daymotorsports.com or pitstopusa.com and order a set of rear single pig-tail springs, typically under $50 each, and exchange the rears. I suggest an 11" x 175in/lb spring and use the isolator.
Or, go to a bigger rear bar - smaller front bar. I would probably chose a bigger rear bar as your front spring rate is too soft to begin with.
If you are "feeling" understeer, then it is massive. The only way I can tell if the car is understeering is with a temperature probe and looking at lap times.
It gets to a point where 1/2 psi adjustments in air pressure is what it takes to podium or load and go home.
06-05-2009, 12:20 PM
#11
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same with the front, i was talking with a tech from hotchkis at the goodguys show this last weekend and they suggested some coil-overs for the front matched with a 750 or 800/lb spring?? would that help out??
i have pics of the car in my fquick page below.
i apriciate all the advise, please keep it coming
06-05-2009, 12:36 PM
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Where are you experiencing understeer by the way? Autox or track?
PS.. I would strongly be selective toward who's advice you consider valid on this subject. MitchNtx knows what he's talking about.
PS.. I would strongly be selective toward who's advice you consider valid on this subject. MitchNtx knows what he's talking about.
Last edited by z28bryan; 06-05-2009 at 12:45 PM.
06-05-2009, 12:43 PM
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I would say that our cars come from the factory with understeer with the stock alignment. Maxing out camber, caster, and going with a reasonable toe = 0 will put more traction to the front tires around turns. You might even get better tire wear over the stock alignment with this alignment spec.
06-05-2009, 01:27 PM
#15
I disagree on the STB and SFC's. Those aren't going to do much to combat understeer.
I would say that our cars come from the factory with understeer with the stock alignment. Maxing out camber, caster, and going with a reasonable toe = 0 will put more traction to the front tires around turns. You might even get better tire wear over the stock alignment with this alignment spec.
I would say that our cars come from the factory with understeer with the stock alignment. Maxing out camber, caster, and going with a reasonable toe = 0 will put more traction to the front tires around turns. You might even get better tire wear over the stock alignment with this alignment spec.
06-05-2009, 03:22 PM
#16
I think the whole thing up to post #10 is hysterical. Mitch's post is pretty accurate, but way premature.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
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06-05-2009, 03:48 PM
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Still wanna know the answer to this! I know a lot of novices in autox yank the wheel full lock and wonder what they can do to the suspension to make themselves turn. I usually tell them driver mod.. take an instructor
06-05-2009, 05:47 PM
#18
Sorry for not contributing but.. yeah that was funny!
Negative camber might help!
06-05-2009, 08:59 PM
#19
I think the whole thing up to post #10 is hysterical. Mitch's post is pretty accurate, but way premature.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
06-05-2009, 09:54 PM
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I think the whole thing up to post #10 is hysterical. Mitch's post is pretty accurate, but way premature.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
Let's see, I've not seen where the shocks are set, what size the tires are, what the pressures are, what the alignment is. All things of CRITICAL importance, and that's just the start.
Last edited by Tdawg; 06-05-2009 at 10:03 PM.