car can not run straight,

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markus_74
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Post Thu May 09, 2013 4:10 pm

hello,

I have re tracking my car and almost all of my front suspension parts are new, but I feel my steering wheel is always go to right, not much but it will go to right so I must counter with my my hand.

I use m3 control arm bushing

I only replace my left control arm but the right still use the old one/

my question :

1.what cause my steering wheel go right?
2.does control arm can bent?
3.does different control arm brand has different angle? my old one is original bmw and the new one is lemforder.
4.does my control arm bent?

This is the data:
front:
caster left 9'24"
caster right 9'36"

camber :
left -1'30"
right -1'12"

Toe:
left 0'09"
right 0'09"

rear :
camber :
left -1'54"
right -0'48

toe:
left -0'12"
right -0'27"

track width different :0.6 inch
wheel base different :0.2 inch
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Chris_B86
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Post Thu May 09, 2013 4:26 pm

Have you still got standard concentric bush on the side you haven't replaced?
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markus_74
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Post Thu May 09, 2013 5:30 pm

Chris_B86 wrote:Have you still got standard concentric bush on the side you haven't replaced?
no, I have replaced all with m3 bush
tha881
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Post Thu May 09, 2013 5:41 pm

Switch front wheels around and see if it pulls left
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Grrrmachine
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Post Thu May 09, 2013 5:43 pm

What's wrong with your back wheels? You've got a huge difference in camber there - your left wheel is almost 1 degree out (-0'48 should be at least -1'30).

Over 9 degrees of front caster is also impressive!

Your front settings look correct, but any issue with the rear will affect your straight line stability. I have exactly this problem myself. It seems you have toe-out at the rear, and -0.27 degrees of toe out will make a significant impact. Both sides should be close to zero degrees toe, or positive, and my geometry guide says rear toe of -0'04" to 0'26" - almost half a degree different to what you have on your rear right side. That may be the problem.
markus_74
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Joined: Fri Jan 26, 2007 11:00 pm
Location: Kudus city, Indonesia

Post Thu May 09, 2013 6:27 pm

Grrrmachine wrote:What's wrong with your back wheels? You've got a huge difference in camber there - your left wheel is almost 1 degree out (-0'48 should be at least -1'30).

Over 9 degrees of front caster is also impressive!

Your front settings look correct, but any issue with the rear will affect your straight line stability. I have exactly this problem myself. It seems you have toe-out at the rear, and -0.27 degrees of toe out will make a significant impact. Both sides should be close to zero degrees toe, or positive, and my geometry guide says rear toe of -0'04" to 0'26" - almost half a degree different to what you have on your rear right side. That may be the problem.
thank you for the info, how to correct this?

I have change the rear bush but never change the big bush sub frame, does the rear sub frame bush is the cause?

or bad wheel is the cause? I use old hartge wheel and some of them had slightly bent at the lip
Last edited by markus_74 on Thu May 09, 2013 6:31 pm, edited 1 time in total.
markus_74
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Joined: Fri Jan 26, 2007 11:00 pm
Location: Kudus city, Indonesia

Post Thu May 09, 2013 6:28 pm

tha881 wrote:Switch front wheels around and see if it pulls left
will try it tomorrow thanks for the advice