Another suspension question?

MovingZen

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I have several suspension mods - adjustable upper and lower control arms, lca relocation brackets, panhard bar, and air lift suspension system. Since I got the new wheels I've had some rubbing issues. The rear wheels are wider, 20x11 with the K1 MPSS 295's. I only rub on the right side, and only in left hand turns. I took the car in yesterday and the rear end is centered. I can stop the rubbing by raising the car(no surprise), and with just about max stiffness in my rear shock dampeners. But, that's only with me in the car. I got up under the car yesterday with the alignment dude, and the only place we could find rub marks was on rear fender rock guard. In this pick, you can see what is causing my problem -

20140823_112158_zpsvdrqczrf.jpg


I'm not trying to drive at this height, it just sticks out more visually. To me, it seems like my rear axle is too far back. I don't think it's centered in the wheel well. What's worse, is that the right side is a 1/4 inch further back by my measurements. I guess dropping the car like that is what pushes the axle back? Will shortening the LCAs help? Thoughts?
 

Tob

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You took the car in and learned that the axle is centered. By your measurements, the right side wheelbase is 1/4" longer than the left. If your front axle centerline is square with the chassis then your thrust angle is indeed off. Did said alignment dude not check any of this? And did he alter the control arm lengths? What brand of relocation bracket are you using?
 

MovingZen

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You took the car in and learned that the axle is centered. By your measurements, the right side wheelbase is 1/4" longer than the left. If your front axle centerline is square with the chassis then your thrust angle is indeed off. Did said alignment dude not check any of this? And did he alter the control arm lengths? What brand of relocation bracket are you using?
He said the axle is centered, and the thrust angle is .18 degrees by the paperwork he gave me after he got done. My measurements are probably not precise, but trying to stick my fingers between the wheel and the fender I can feel the difference to back up my eyeballed measurements with a tape measure. It's definitely tighter on the right side. It also helps me understand why I'm rubbing on my right and not my left. All my suspension parts are BMR or Air Lift Performance. He didn't alter anything under the rear, but suggested I take it to another shop that specializes in race suspensions. He felt that if he started messing around it could get out of hand and didn't want to screw things up worse. I plan on going by the other place next week, but want to try to get a better understanding of what needs to be done before I do. These are the guys he told me to take the car to - http://www.autometricsmotorsports.com/ I called them yesterday, but the lady who answered the phone said all the techs were at VIR. She took my name and told me that they would call me on Monday.
 

MovingZen

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Crap, I figured out why the difference between the sides. The air lift compensates for me in the car, when I'm not in the car the drivers side is higher than the passenger side by 1/2 an inch. I put my wife in the car and even though she is nowhere near my weight the drivers side fender dropped down and closer to the tire. That explains why the thrust angle is good and my dumb ass is wrong.
 

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