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too much understeer now!

I put 9x19 and 9x11 wheels with 255/35 and 295/30 hankooks with eibach springs and now have too much understeer. the alignment specs post spring install show -1.3deg and -1.4deg

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Old 11-14-2010, 05:15 PM   #1 (permalink)
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Default too much understeer now!

I put 9x19 and 9x11 wheels with 255/35 and 295/30 hankooks with eibach springs and now have too much understeer. the alignment specs post spring install show -1.3deg and -1.4deg camber in the front.

can I get more negative camber out of the front with the stock bits? if so, what is suggested to relieve the understeer based off the tire sizes I am running? also, at what point do I start getting tire wear because of too much negative camber?

would sway bars help my situation at all?

thanks.
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Old 11-14-2010, 06:36 PM   #2 (permalink)
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Stiffer rear sway bar will help.
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Old 11-14-2010, 08:25 PM   #3 (permalink)
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Quote:
Originally Posted by zero View Post
Stiffer rear sway bar will help.


You could also try removing the front strut bar.
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Old 11-14-2010, 11:55 PM   #4 (permalink)
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could also run a couple psi more tire pressure in the rear... some combination of the above... curious why you went with such small tires on the front
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Old 11-15-2010, 12:07 AM   #5 (permalink)
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Strange, when you lower the car you automatically get more negative camber. In the front that should give you better turn in. You can get a front camber kit to add more negative camber in front...closer to -2.0.

I wouldn't remove the front strut tower bar. Reducing structural rigidity is not the answer.
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Old 11-15-2010, 02:14 AM   #6 (permalink)
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I do run a couple more psi in the rear.

255/35's are a perfect fit for the 9" wheel.


Quote:
Originally Posted by travisjb View Post
could also run a couple psi more tire pressure in the rear... some combination of the above... curious why you went with such small tires on the front
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Old 11-15-2010, 02:15 AM   #7 (permalink)
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Quote:
Originally Posted by djpathfinder View Post
Strange, when you lower the car you automatically get more negative camber. In the front that should give you better turn in. You can get a front camber kit to add more negative camber in front...closer to -2.0.

I wouldn't remove the front strut tower bar. Reducing structural rigidity is not the answer.
I think the problem is strictly do to the tire size ratio between front and rear. there's just too much in the rear, which makes the front push. I'll probably just get a camber kit I guess.
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Old 11-15-2010, 08:48 AM   #8 (permalink)
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Did you change the offset significantly? Changing the track, especially if you didn't change it evenly in the front and back, may have affected your handling.
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Old 11-15-2010, 09:01 AM   #9 (permalink)
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Originally Posted by vortrex View Post
I think the problem is strictly do to the tire size ratio between front and rear. there's just too much in the rear, which makes the front push. I'll probably just get a camber kit I guess.
The 2 inch wheel width stagger is doing you in.

Increase front camber to -2.0 degrees using a camber kit. You'll go through tires a little faster if you do a lot of highway but it won't be that bad. Sway bars would probably only make it worse as pretty much all the aftermarket kits increase the front bar stiffness more than the rear. You could also try widening the front track by adding front spacers or narrowing the rear track by removing spacers if you used any there.
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Old 11-15-2010, 12:05 PM   #10 (permalink)
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yah, wat offset are you running? your rear might be pushed out too far vs your front.
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Old 11-16-2010, 02:14 AM   #11 (permalink)
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running 19x9 +24 front, 19x11 +23 rear offsets. I think this is the most aggressive fit you can get from forgestar. I too think it's more of a issue with 9" in the front and 11" in the rear and the resulting tire width differences. I'm just wondering if a camber kit can help this if I went to -2.0? I do commute a lot in this car, 70 miles per day.
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Old 11-16-2010, 07:59 AM   #12 (permalink)
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I have the Forgestars but I have the 10" wheels up front, 11" in the rear.

What are you running for tire?

When do you experience the understeer, is it turn-in or mid corner?
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Old 11-16-2010, 01:21 PM   #13 (permalink)
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Quote:
Originally Posted by ChrisSlicks View Post
I have the Forgestars but I have the 10" wheels up front, 11" in the rear.

What are you running for tire?

When do you experience the understeer, is it turn-in or mid corner?
I don't think they make a 19x10 wheel anymore.

I have the Hankook V12 tires.

understeer is turn-in, really all the time. I just feel all the weight of the car on the front wheels and in the steering. it pushes a lot.
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Old 11-16-2010, 01:25 PM   #14 (permalink)
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More negative camber up front should help with the turn-in, but really it's going to be difficult to overcome that amount of tire stagger. Ideally you would maintain the OEM ratio or decrease it.

FWIW, you can fit up to a 275 width tire on a 9" wheel.

You could also leave the OEM sway bar up front and run a stiffer rear bar, but that will mostly help center-off.
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Old 11-16-2010, 02:05 PM   #15 (permalink)
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I think you should change the tire size to one of these combo.

F 255-40-19 R 285-35-19

or

F 275-35-19 R 305-30-19

I prefer the first one since 2nd combo is way too much in my onpinion for the stock setup and power.
Generally speaking, if you over size the tire too much, you might get a nicer look, but you not only eat at your power but it can also tend to numb the feel of the vehicle.

Last edited by s30z; 11-16-2010 at 02:31 PM.
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