Lower Control Arm Problem

[SeanC]

Hey guys,

I installed UMI adjustable lower control arms (poly/rod end) a while back, and the wheels never looked properly centered in the wheel well. I made sure I matched the length of the control arms to the stock ones (laid them on top of eachother and put bolts through both holes). The wheels are sitting towards the back of the car to the point of barely being able to put my hand between the tire and edge of the rear bumper.

I tried to adjust them today, and I pushed the rear towards the front of the car to center it (used a tape measure to center it the best I could). Because I moved the rear forward, I had to shorten the length of the control arms. Finished both sides, lowered the car, and they are almost exactly the same position as before!!! How is this possible? I really dont get what the problem is...I just can't make sense out of it. I told someone at UMI about the problem and they looked at me like I had 4 eyes...

Any ideas?

[//<86TA>\\]

Hey guys,

I installed UMI adjustable lower control arms (poly/rod end) a while back, and the wheels never looked properly centered in the wheel well. I made sure I matched the length of the control arms to the stock ones (laid them on top of eachother and put bolts through both holes). The wheels are sitting towards the back of the car to the point of barely being able to put my hand between the tire and edge of the rear bumper.

I tried to adjust them today, and I pushed the rear towards the front of the car to center it (used a tape measure to center it the best I could). Because I moved the rear forward, I had to shorten the length of the control arms. Finished both sides, lowered the car, and they are almost exactly the same position as before!!! How is this possible? I really dont get what the problem is...I just can't make sense out of it. I told someone at UMI about the problem and they looked at me like I had 4 eyes...

Any ideas?

when you moved the axle to the centered position, was the suspension loaded, or was the rear hanging? the axle moves in an arch, so when you drop the rear it will move.

[deadtrend1]

Just make them the same length as the stock ones were. There really is no need for adjustable LCA's unless you are running really really ridiculously big drag tires.

Adjustable PHB if car is lowered. But that would be about it.

[SeanC]

I had a jack under the rear to put a little compression on it, but it definitly wasnt under the full weight of the car...If i jacked it up too far I couldn't move it anyways....

How are you suppose to have it? What I dont get is why my tires are still back too far towards the rear of the car....I have the rod end turned in much further than before (shortening the LCA). Even if I had the suspension completely unloaded, wouldnt this still pull the rear forward?

And the problem is that IF I keep them at the stock LCA length, for some reason the rear just looks off. I'm not being picky, but I know for a fact that it isnt right. You can tell that there is a big difference...I've asked numerous people to tell me what looked wrong with the rear wheels and they said they were not centered in the wheel well...

[deadtrend1]

are you running relo brackets?

[SeanC]

Yes, I have relocation brackets (bottom hole). The car is stock height too..

[deadtrend1]

Bolt in I assune, go to the middle hole

[SeanC]

Yeah they are bolt in....What would going to the middle hole do (not to question your advice)?

I really want to keep it in the bottom hole to have them be most effective....I dont see any reason why the bottom hole wouldnt work.. :?:

[deadtrend1]

Stock suspension worked for years as is. Relo brackets aren't really necessary, unless you are lowered extremely and in that case it MIGHT be a good idea to use the bottom one.

[SeanC]

okay....how is moving to the middle hole going to fix the problem though??? I'm not understanding why when I adjust the length of the LCAs why the rear isnt moving accordingly...

[sweetbmxrider]

make sure you aren't bottoming out the drive shaft or binding the torque arm

[KirkEvil]

make sure you aren't bottoming out the drive shaft or binding the torque arm

^I would def check out this, especially the DS.

Moving to different holes on relo brackets will not change anything...The lower mounting holes are actually moved forward to account for the swing radius of the LCA's.

You have to realize that when you took off your stock LCA's to line them up with the new, they were not loaded. The stock rubber mounts will compress MUCH more than a poly/rod end mount. That is why you originally had the tires pushed back. I cant explain why you cant adjust, haha.

fyi, I have 1.75" clearance between the tire and rear/front body panels to center a 26" tall tire.

[SeanC]

This is a dumb question, but how can I tell if the DS is bottoming out? Will it be obvious by looking at it?

Now i'm all worried that I'm damaging something and i'm suppose to take my car to the track for the first time Saturday :-?

[KirkEvil]

Just look at it, check the TA rubber mount too. Theres really no reason for it to be bottomed out since your tires are actually too far back.

Do you have a stock rear?

[SeanC]

Yup stock rear....ill take pictures later today so you guys can see the position of the wheel in the wheel well. I'm really at a loss...lol. just doesnt make sense

[KirkEvil]

How much did you pull in the rod end since aligning them with the stockers? and how much adjustment do you have left?

[SeanC]

I'm honestly not sure how much shorter I have them now than the stock ones (adjusted them a few different times). Right now I have about 4 threads on the rod end exposed....I honestly can't shorten either one anymore (for some reason the threads are screwed up. I had trouble getting them that short to begin with...I just couldn't believe I made them that short and the wheels still seem to be too far back?

[KirkEvil]

Have you looked under the car to make sure the TA hasnt popped out of the rubber bushing off the trans?

[sweetbmxrider]

i'm interested in a pic but you could have a bent mount somewhere possibly causing a bind. you could try going real drastic and shortening the lcas by say 2 inches just to see if the rear pulls forward.

[SeanC]

I'd be extremely surprised if the TA is out of the rubber mount, but i'll definitly check it out when I get home from work. And as far as shortening the LCAs by a lot to see if it pulls forward...wells that what I thought I did yesterday lol

yesterday I did each side one at a time...took one off, pushed rear end forward until the measurements from each body panel were equal, set the lower control arm length to match the hole, and bolted it up...I can't say for sure that it didn't move at all, but it still is back towards the rear.

I want it to move forward, but i'm also worried my tires are going to rub on the inner fender in the front (18" c5 rims)

[sweetbmxrider]

moving the rear forward won't affect the front suspension in that way.

you should make reference points on the frame that are equal on both sides and measure that way. use 3 points of reference too. body panels can be off.

[SeanC]

Okay, ill try that. I was worrying about my rear tires rubbing (not the fronts). Sorry I didnt word my last post very well...I should have wrote "rub on the inner front part of the rear fender"

[sweetbmxrider]

ah ok, i took a hammer to my inner fenders in a few spots when i had the 18 x 10.5's on

[SeanC]

Here are the pictures (sorry they're not very good...from my cell phone). It seems like they look better than they did, but they still do not look centered...you can see the front inside part of the wheel wells so well...

http://i90.photobucket.com/albums/k271/SeanCZ06/IMG00030-20101028-1635.jpg

http://i90.photobucket.com/albums/k271/SeanCZ06/IMG00027-20101028-1634.jpg

[V]

im tired after a long work day but if you think about it... all you'll really doing by shortening the rear lca is adjusting angles, not really pulling the rear closer. the 10 bolt main housing is a set distance from the tailshaft of the trans. the TA is bolted to the rear and attached at the trans... you'd, in theory, need to shorten that there to bring the wheels forward.. by shortening the LCAs, you are just really rotating the rear axle housing and changing the pinion angle.

now i know with my adjustable TA, i could adjust the front rod end and make many more adjustments

[sweetbmxrider]

im tired after a long work day but if you think about it... all you'll really doing by shortening the rear lca is adjusting angles, not really pulling the rear closer. the 10 bolt main housing is a set distance from the tailshaft of the trans. the TA is bolted to the rear and attached at the trans... you'd, in theory, need to shorten that there to bring the wheels forward.. by shortening the LCAs, you are just really rotating the rear axle housing and changing the pinion angle.

now i know with my adjustable TA, i could adjust the front rod end and make many more adjustments

the drive shaft can be pushed further into the trans to a point and the stock torque arm mount is open so you can go further into it to a point as well.

honestly the pics don't look bad to me. the trans am bumpers tuck in closer than the camaro bumpers. i dono i wouldn't be too overly concerned with it if what you tried hasn't changed anything. you need to keep many other things in alignment back there so stock length + or - an inch is probably as far as you want to go. just my thoughts.

[KirkEvil]

the drive shaft can be pushed further into the trans to a point and the stock torque arm mount is open so you can go further into it to a point as well.

honestly the pics don't look bad to me. the trans am bumpers tuck in closer than the camaro bumpers. i dono i wouldn't be too overly concerned with it if what you tried hasn't changed anything. you need to keep many other things in alignment back there so stock length + or - an inch is probably as far as you want to go. just my thoughts.

I agree with sweetbmxer. The DS and TA are able to be pulled in to a point. Your wheel's position look good to me.

[SeanC]

Maybe the adjustment did help a little...I really appreciate your guys help. I'll leave them alone for right now!