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Help me with my alignment

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Old 03-28-2011 | 07:17 PM
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Help me with my alignment

I'm looking for some advice to improve my alignment for Autox.

Currently:
Front Camber -1.3
Front Caster 7.0
Front toe 1/16 out

Rear Camber -2.2
Rear Toe 0

I have driven a few events with this setting and I find less high speed stability and excessive oversteer on trail braking. I have been driving on street tires but I will be switching between street and A6 in the summer. Should I:

A) decrease rear camber to lets say -1.5
B) 1/32 toe in
C) Both
D) Other suggestions
Old 03-28-2011 | 07:59 PM
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More rear Toe-in. I run about 3/16" which I think is close to the factory setting.

Jim
Old 03-28-2011 | 08:28 PM
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You want more negative camber in the front for autox...Most of the time.

-3 F and -2.5 R is what i'm at. -2.2 front and -2 rear would be a good setup for you.
Old 03-29-2011 | 01:41 AM
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Jim, I always thought 1/32 in was the stock setting... isn't 3/16 a little too much?

Also -1.3 was the most I could dial with the current caster... I might have to reduce caster first then.
Old 03-29-2011 | 02:26 AM
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Originally Posted by bentiac
I'm looking for some advice to improve my alignment for Autox.

Currently:
Front Camber -1.3
Front Caster 7.0
Front toe 1/16 out

Rear Camber -2.2
Rear Toe 0

I have driven a few events with this setting and I find less high speed stability and excessive oversteer on trail braking. I have been driving on street tires but I will be switching between street and A6 in the summer. Should I:

A) decrease rear camber to lets say -1.5
B) 1/32 toe in
C) Both
D) Other suggestions
I've got about the same toe front and back, but when my camber was yours, I just got a lot of understeer, and at the same time no start moving rear traction.

Anyhoo, lower the rear camber to -1.5 if you can; my stock sport 07 auto would only go down to -1.65, and I got about -1.7 front right.

So now with cambers close all around, I've gotten it to give oversteer only when turning AND accelerating on a wet road.

I can't get my rear Hankooks Ventus V12's to slip under any other condition, and the front tires are wearing slightly more than the rears, instead of the first set of SPT's where the rears wore twice as fast.

My rear suspension and shocks is definitely working because I'm not wanting anything changed, but with your trail braking complaint, your rear shocks and/or ride height might be fubared.

The minimum ride height specs are 13.9 inches rear, and 14.2 front which is exactly where mine is stock.

Last edited by REDRX3RX8; 03-29-2011 at 02:35 AM.
Old 03-29-2011 | 07:01 PM
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Originally Posted by bentiac
Jim, I always thought 1/32 in was the stock setting... isn't 3/16 a little too much?

Also -1.3 was the most I could dial with the current caster... I might have to reduce caster first then.
I have to double check the manual, but that's where mine was when I checked it the other day. Could explain why my street tires were wearing out the inside edge, but I thought it was the 1/4" toe out at the front!

Less caster will allow a little more camber at the front which is desirable for AX. The other recommendations on this thread are valid in general, but to address the specific symptom you describe (trail braking oversteer) I would add rear toe in first.

Jim
Old 03-29-2011 | 10:07 PM
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^ I accidently got a slight toe out on the rears from my first alignment with about -1.6 camber front, and -1.9 camber rear.

That rear toe out didn't seem to cause any rear bad manners on the track, and I've always tended to trail brake some.

bentiac, is it possible that you've got the brakes on the rear working better than the fronts, since by now you've probably bought non stock pads?

Also, I had a smaller tire on the front, and my rear brakes got confused with the traction control, and locked up spining me quick at 30mph.
Old 03-30-2011 | 10:40 AM
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it doesn't sound like your alignment is causing the problem.

i am able to get only ~-1.1* of so in the front, no matter where the caster is set.

my settings (Stock class) are:

front
Camber: -1.1 (most i could get)
Caster: +6.5
Toe: 1/16" out per side

rear
Camber: -1.5 (that is the least i could get)
Toe: 1/32" out per side

with that setup on street tires it is a little pushy in low-speed sweepers, but turns in nicely and is balanced at higher speeds. on r-compounds, it works well, and tire wear and temps (on 285s) are pretty even.

Originally Posted by TopGear8
You want more negative camber in the front for autox...Most of the time.

-3 F and -2.5 R is what i'm at. -2.2 front and -2 rear would be a good setup for you.
that much negative front camber is almost certainly not possible unless the car is lowered.
Old 03-30-2011 | 12:28 PM
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Well thanks for all the feedback... the one thing common is to bring the camber angles closer together either by reducing it in the rear or increasing it in the front. I'll try that. I was also told by the guy who did my alignment who is also a long time autocrosser that no toe in the back will be a problem on high speed courses but might be alright for slower, tighter sections.
Old 03-30-2011 | 12:46 PM
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^^Well mike he never said if he was lowered or not...Did he...
Old 03-30-2011 | 02:32 PM
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From: Philly
fair enough.

Originally Posted by bentiac
Well thanks for all the feedback... the one thing common is to bring the camber angles closer together either by reducing it in the rear or increasing it in the front. I'll try that. I was also told by the guy who did my alignment who is also a long time autocrosser that no toe in the back will be a problem on high speed courses but might be alright for slower, tighter sections.
maybe. mine is at zero toe in the back now (not much autoXing on tap this year) and it was perfectly fine at a track day last weekend on street tires. with the toe out i had last year (w/ Hoosiers), i didn't find it to be loose in high-speed elements. you'll really need to try it out for yourself to see what works best for you. toe is really easy to change and measure, so you might as well experiment.
Old 03-31-2011 | 04:10 AM
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For those of you who can't reach your desired camper settings, try a pry bar or use your feet to push the tire in or out while you tighten the adjusted bolt. A little force is usually good for .3 degrees.
Old 03-31-2011 | 04:16 AM
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Originally Posted by dmitrik4

that much negative front camber is almost certainly not possible unless the car is lowered.
Sure it is. Just need the drop engineering lower brushing.
Old 03-31-2011 | 07:57 PM
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FYI, if anyone still cares, the factory spec (at least on the '07) is .12"+/-.11" toe in at the rear, which is basically 0 - 7/32".
Old 03-31-2011 | 09:23 PM
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From: Philly
Originally Posted by Highway8
Sure it is. Just need the drop engineering lower brushing.
or custom control arms. sheesh...OK, fine. it's not possible in Stock-legal configuration.
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