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Upper A body control arm question

4K views 12 replies 5 participants last post by  Lemans guy 
#1 ·
I bought a what I believe to be a Helix 64-67 GM A Body control arm set at the Turkey run in Florida. After installing the kit with a Right Stuff disc brake kit it seems to me that the geometry does not seem quite right. When I install the tire on the vehicle the rear of the tire comes real close to the bottom of the fender. Is it possible that I could install the upper A arms on the wrong side? I lined up the new A arms with the old ones as I installed them. So I don't believe they are in wrong. I'm just not sure what to think. Any suggestions would be appreciated.
 

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#4 ·
The tires are still close to the back of the fender. couldn't drop the car down all of the way because I tires are 14" and now with the new brake kit I need 15" tires. The picture does have a 15" tire that I borrowed from another car. Maybe I should put those rims on both sides and drop the car down and check again. That's another issue, the guy who sold me the brakes told me that 14" tires would work. They don't, when you put the rim on it hits the brake caliber.
The brake calibers are facing towards the rear of the car.
 
#5 ·
Mixing branded parts that were not meant to be pieced together might be the problem. I checked on the Helix website and they do not give very much of the specific details on the control arms, BUT, under the description of the A-arms it does say "Feature: Improves Suspension Geometry" which typically indicates that these arms are not the same as the stock pieces. I see that they seem to sell a kit having the 2" dropped spindles which would put the tire higher up into the wheel well which would most likely eliminate your tire rubbing problem.

Some kits use the taller Camaro or Big Car spindles to operate correctly. Again, could be you do not have the correct and needed parts to make this all work.

Later Pontiac rims which are 14" and designed to fit front disc brakes will fit. Earlier rims such as the original ones on your car will not. This has been covered on the forums a number of times. I have a front disc brake conversion on my '68 Lemans project and the stock 14" rims will not fit, but grabbed a set of later 14" rims made for disc brakes and they fit just fine. I believe they are also deeper, ie wheel back spacing which can also be something to look into to eliminate the tire rubbing.

I suggest you go on the Helix website and they do have "Live Chat" as I was hit up with it when I was searching for info. Talk with them directly and I would think they would know exactly how to solve your issues rather than guess or become frustrated with the set-up. It is important to have all your parts matched, a-arms, spindles, spring height/rates, etc. or you may find yourself with an evil handling car that may let you down at the worst possible time and put you off the road at best or in a tree at worst. Don't just guess and piece things together because it was a "deal." Get the answers from the experts who made the parts. :thumbsup:
 
#8 ·
noreast...Did you reinstall the wheel alignment shim Kit? I am sure you did but just checking, caster and camber shims tilt the wheel...Caster is the front to back tilt, camber is the side to side tilt, The shim pack must be installed and sort of close then you make final adjustments,...too much positive caster tilts the wheel back.

no shim kit will make a mess of things sometimes.....
 
#9 ·
I got an email from Helix. They said that the control arms are the same length as the stock ones. He did say that the after market brake kits push the wheels out about an 1". I believe that the right stuff kit says 1/2". He also said he would forward my email to the suspension specialist. Have not heard from him yet.
In response to Lemans Guy's post. I did put the original shims back in, but not sure if all of them are in.
I know this may seem crazy but I can't help to wonder if I switched the passenger side upper arm with the drivers side upper arm it might move the spindle forward a little bit. I'm not a suspension expert and don't know if that would make a difference or not. Any ideas on that thought?
Also want to thank everyone for the posts trying to help.
 
#10 ·
Don't know if that aftermarket kit is switched side to side possible I suppose...I have the right stuff disc brakes and 15 inch wheels fit fine, but A-ARMs are new stock......

Also you will have to load the suspension to see and have the shim kit in to start,..whatever helix says they recommend on shims with their arms.

Shims change the tilt of the wheel,.....
 
#11 ·
I checked again today. The arms are in correctly. The bump stops line up correctly and the match the shape of the original A arm. Put 15" tires on the car with a 3 3/4" backspace rim and the tires will just hit the fender when turning. That's with the weight of the vehicle on the tires. Everything else seems to work perfect. I can't help but think that back spacing on the rims and or maybe a dropped spindle might be the way to go. Just don't want to keep throwing different parts at the car. I have added a few pictures of the car as it sits now. Anybody have any ideas? I really don't know what to do next.
 

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#13 ·
So I measured mine for you, it is about 1 3/4 on each end, yours looks tight in the back, so you can see what your front measurement is.

I think you may just have too much positive caster, that is the tilt of the wheel back, as yours is, from the vertical. Those adjustments are made by shim packs, uneven shims front to back on the same wheel change caster......at the top of the A-Arm

Your alignment cannot be right given the changes you made.......can you align it yourself?

If not can you drive it to a nearby shop and get it aligned,....start there, if they cannot align it than the offset upper control arm that Pontiac Jim recommended.....

Also correct springs and shocks are needed...but reducing positive caster by shims may help a little to tilt that wheel forward....

So if you can get it aligned at home or at the shop, or ask Helix what shim pack widths they recommend to start with....

You will get it!
 
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