mxt_77

So, I took my car in for an alignment the other day to get a more aggressive alignment done. The guy told me that on the Left Rear he was not able to get as much camber as I wanted (-2.0). He said that he could only get -1.0, unless I wanted to have toe-out (since the toe and camber adjustment affect each other). I wasn't really surprised, and attribute this to an accident I had over a year ago (the car hadn't been re-aligned since the repairs were done). So, I had him match the right rear to the left rear with a little extra negative camber on the right to adjust for driver weight, and I took the car home with the intent to replace the suspect parts (control arm, knuckle, etc).

However, after the alignment I notice that the suspension feels "unsettled" when I make gentle right hand turns at speed (around 55-70mph), for example, when I change from the left lane to the right lane, or when I'm going around a gentle right hand sweeper. It kinda feels like the car starts to turn into the corner and it plants for a moment, then slips then plants again, and then it usually settles in unless I adjust steering input.

Does anyone have any ideas of what might cause this? My first assumption was that one of the adjustment bolts was not tight, and things were shifting around when the left side got loaded, but I checked all of the bolts and they were tight. I can't think of anything else that would cause this sensation.

Anyway, if it helps, here are my alignment specs:
Before:
[CODE]
Front:
Camber:

SEVNT4

Is it possible that the car didn't change camber on the left as much as you expected it to when you got in? it sounds like a small amount but might be enough to feel unbalanced. I don't have my numbers but it's a semi-aggressive alignment on mine and i get that sensation when digging into a turn. At first, it feels unsettled but it plants itself with a little throttle.

on a side note, I checked my tire pressure today and one of the rear tires was 3-4 psi less than the other tire and that made it also feel a bit like what you described. Have you checked pressures too? After I equalized pressures, it felt a bit more stable.

mxt_77

Yeah, my tire pressures are good. I've checked them multiple times since I first noticed this problem. Generally when my tire pressures differ, the car pulls left or right under accelleration. Currently, the car tracks perfectly straight under accelleration & braking.

03_AP1

your "after" specs seem LESS aggressive than the stock figures if memory serves me correct....

Isn't it -1.5 degrees on the rear from the factory?

mxt_77

Yep... but like I said, the mechanic couldn't get that much camber, likely due to previous damage.

cdelena

The lack of rear toe in will make it harder to keep the rear behind you.. that may be what you are feeling. I would find a way to get more negative camber and run a bit more toe in on the rear.

mxt_77

I would agree... but unless I'm misreading the numbers, I had toe out before the alignment, and now I have a hair of toe-in. The car felt fine before the alignment.

cdelena

I don't think so.. toe-in is the only spec I have ever seen for the rear (toe out would make no sense) and those numbers look like that is what you had.

hboy7777

i usually add toe out on rear to make cars track better. 0 toe in rear makes cars very sensitive to road crown and slopes, toe in makes cars feel "unplanted and unpredictable". i would go with at least -2 camber in front,(if autocrossing) if street only leave it.. and more toe out in front also .05 each side. -lets car track alittle more predictable. definately need more camber in the rear, but that will come when u get it fixed..

mxt_77

I dunno. Looking at the little diagram on my spec sheet (a little picture that indicates what the value is actually measuring), it appears that a negative value here would be indicating toe-in. Additionally, I tend to think that it is toe-in due to the fact that even though it feels "unsettled" under light loading, the car seemed much less tail-happy in corners at the last autocross.
I'm having to replace the knuckle/hub/bearing anyway, so when I take it back in to get it re-aligned with the new parts I'll actually ask the operator which one is positive and which is negative, just to be sure.