Front compression control arm rubbing

[inTgr8r]

Hey guys, just got the car out for the first track session up here this year.

I have just installed MCS suspension on the car and running 18x10 et25 wheels.
I'm running into a rubbing issue on the front compression control arm
It only happens when the wheel is turned in.
The wheel rim rubs on the arm

I'm using a 5mm spacer and clear the strut spring/perch no problem.
I tried a 12mm spacer but it still rubs.
I'm running max castor on Vorshlag plates to get as much dynamic camber as I can, & I think that may be the cause.
Static camber is -2.6

I'm sure this isn't something new to you guys and wondering what you've done about it.

I think more neg camber would change the angle and give more clearance but i'm close to the limit w/o opening up the tower hole a bit.
(which I'm reluctant to do)

raising the car would also change the angle and may provide more clearance as well.
I'm 1/2" lower than ZCP spec right now.

the other option is to file down the control arm a bit.
...also not great.

any and all feedback on the best solution is appreciated.

[Melchior]

Your tension rods are installed upside down, which looks to be limiting clearance. I have 10.5” +27 up front, which go ~8mm further to the inside, and I still don’t rub at full lock.

[dogbone]

Originally Posted by Melchior

Your tension rods are installed upside down

haha! You beat me to it! I was so confused looking at that picture that I finally went and jacked up my stock suspension street E92 M3 and took this pic. Yup, it's mounted upside down.

[inTgr8r]

Originally Posted by Melchior

Your tension rods are installed upside down, which looks to be limiting clearance. I have 10.5” +27 up front, which go ~8mm further to the inside, and I still don’t rub at full lock.

Originally Posted by dogbone

haha! You beat me to it! I was so confused looking at that picture that I finally went and jacked up my stock suspension street E92 M3 and took this pic. Yup, it's mounted upside down.

well.... slap me silly

I had the whole front end off doing rod bearings among other things before track this weekend.

LOL... too many midnights in the shop

Thanks!!!!!!

[dogbone]

Originally Posted by inTgr8r

well.... slap me silly

I had the whole front end off doing rod bearings among other things before track this weekend.

LOL... too many midnights in the shop

Thanks!!!!!!

btw, I don't think it's just mounted upside down. Looking at the comparison of the two pics, I think it's mounted to the wrong spot too, which means other stuff is being affected as well. Better get under there and inspect what's going under that car.

[Melchior]

You will also need to realign everything when you swap everything back

[inTgr8r]

Originally Posted by Melchior

You will also need to realign everything when you swap everything back

yeah thanks, thats no problem, I do all my own alignments anyway.
I'm always tweaking things.

[inTgr8r]

Originally Posted by dogbone

btw, I don't think it's just mounted upside down. Looking at the comparison of the two pics, I think it's mounted to the wrong spot too, which means other stuff is being affected as well. Better get under there and inspect what's going under that car.

No, its in the right place just upside down.

My pic is from the right side suspension and looking from the front towards the rear.
It just looks weird

[dogbone]

Originally Posted by inTgr8r

No, its in the right place just upside down.

My pic is the right side and looking from the front towards the rear.
It just looks weird

hehe maybe I am confused, but look where your arm connects. It connects to the absolute BOTTOM of the upright/knuckle. Look where mine connects, it connects NOT at the bottom of the upright/knuckle. On mine, a straight control arm connects to the bottom. Am I seeing it wrong?

Let's put it this way, if you flip that arm upside down, I don't think you will be able to mount it to the same place.