[gtorich]

Not sure if this happened before the alignment or after the alignment.......i know i cut the dust shield too close to the lower arm, that was rubbing, so i cut another half inch off each side..........thats when i noticed this scratch on the back of the rotor. Pass side has just a slight scratch, you cant get you finger nail in it...........drive side, not that a scratch.

I can get a 0.50 shim between the control arm and the rotor, maybe a hair more, not sure if its supposed to be that close. So im hoping it was the dust shield that did this.........i assume someone would have noticed this on the alignment , so im thinking it happened after.

To try to make my usual long stories short...........what do you think of this plan, take a marker and fill in the scratch, take the car out and see if anything happens to the marker.

Final question, i know this wouldnt fly on the brake pad side, but do you think this mark is in any way unfit to drive the car.


This is a umi aftermarket arm.

Rich

[Sirrotica]

You'll be fine with that small groove, the original GM rotors had a groove cut in them from the factory much deeper than that minor groove. Later on the aftermarket quit cutting those grooves in them because it was just another machining operation they could cut out for more profit. The brake pads will wear so there is contact with the groove, you'll be just fine. In my experience there is no safety issue to worry about.

[ZeGermanHam]

To my eye, the control arm looks too close for comfort, but it's hard to see from the photos. Something is awry here. What is actually rubbing? The control arm against the rotor? See the attached photos of my car with UMI control arms. Notice there is plenty of daylight between the control arm and the rotor surface.

Also, when you say the following...

Originally Posted by gtorich

Final question, i know this wouldnt fly on the brake pad side, but do you think this mark is in any way unfit to drive the car.

What do you mean by "the brake pad side"?

[gtorich]

Hey thanks Brad & Karl for the reply.........sorry about the confusion by the brake pad side, i should have said the backside of the rotor..........on those arms i have the # 4031-1.....i see you have the same end links that i have, im working with Ramey right now on my other issues with those, i can not get those to fit without my sway bar hitting the tie rods....we have the same cars...........except parts fit better on yours. lol

I'll email you some other pics and the align numbers, maybe we can figure this out yet.

Rich

[ZeGermanHam]

I forget, are you still using B-Body spindles, or did you scrap them and buy A-Body spindles?

[gtorich]

Originally Posted by ZeGermanHam

I forget, are you still using B-Body spindles, or did you scrap them and buy A-Body spindles?

Yep, switched everything over to the A-Body stuff..........the spindles are oem not aftermarket, im gonna take another look at it today, mark the rotor, im assuming if its hitting the rotor the mark should come off quick..........dont think the brake pad will wipe it off right away seeing its gouged at little back there.

If its hitting the rotor, seems the only other options i have is # 1. Grind off some of the control arm..........dont think this is the wisest decesion. # 2. put some kind of spacer in the cross shafts to make the wheel come out a little further.........problem with that i assume then the wheel will be hitting my inner fender......

Ramey from umi is suppose to be back monday, hopefully with some news of my end links issue............havent even mentioned this mess to him. lol

Cant thank you guys enough for the help im getting here, hopefully i can get this straighten out.

Rich

[gtorich]

Trying to give as much info as i can, the rotors are for a 69-72...believe they are 1 inch thick, will have to double check on that.

Rich

[gtorich]

Ok, i know im driving you guys nuts with this, but hang in there. lol

Marked the little gouge today, took the car around the block, when turning left into the driveway, my wife got under the front wheel and said she couldnt get a fingernail between the rotor and lower control arm..........so it wasnt the dust shield doing the damage.

Might help if i give you guys some more ingo

Upper arms spc adjustable
Lower arms umi
Springs are 1 inch lowering from eaton.........went with the 1 inch because everyone said the stock springs were too high and needed cutting.........my car always sat somewhat low and i lliked that look.

11 inch rotors, width is 1.05 according to speedway motors......i measure 1.60 ish

The gap you see in the pics between the rotor and lower arm is with the car jacked up............when level i only get 0.50 maybe a hair more.

Little depressing with the upper & lower arms, springs/ball joints.......got about $1800 in this set up and cant get around the block without wrecking the rotors. wow

Couple pics for you.................hopefully someone can shed some light on this deal.

Rich

[Sirrotica]

Originally Posted by gtorich

Ok, i know im driving you guys nuts with this, but hang in there. lol

Marked the little gouge today, took the car around the block, when turning left into the driveway, my wife got under the front wheel and said she couldnt get a fingernail between the rotor and lower control arm..........so it wasnt the dust shield doing the damage.

Might help if i give you guys some more ingo

Upper arms spc adjustable
Lower arms umi
Springs are 1 inch lowering from eaton.........went with the 1 inch because everyone said the stock springs were too high and needed cutting.........my car always sat somewhat low and i lliked that look.

11 inch rotors, width is 1.05 according to speedway motors......i measure 1.60 ish

The gap you see in the pics between the rotor and lower arm is with the car jacked up............when level i only get 0.50 maybe a hair more.

Little depressing with the upper & lower arms, springs/ball joints.......got about $1800 in this set up and cant get around the block without wrecking the rotors. wow

Couple pics for you.................hopefully someone can shed some light on this deal.

Rich

From the picture, it looks as though the lower control arm is made incorrectly. The outside of the ball joint socket seems to be canted towards the outside of the car. As it swings in an arc under suspension compression it contacts the rotor surface. If the spindles are GM units (not aftermarket) then the lower control arm has to be made incorrectly. I'm not there to lay eyes on it, but from the pictures thats what it looks like to me....

[gtorich]

Hey brad, im lost again, what pic are you talking about...........the spindles are from a 69 chevelle.........oem...........the lowers are from umi, supposed to be usa made, something isnt right here, thats for sure.

I just sit here shaking my head and saying................this shouldnt be his hardl lol

Rich

[Sirrotica]

Second picture, it looks as though the tube that the ball joint is pressed into is canted towards the rotor and as the lower control arm goes upwards it lessens the distance between the lower edge of the tube and the face of the rotor contacting each other. As the lower control arms pivots downward the gap opens.

Being you've used GM spindles that eliminates the possibility of the spindle being the problem.

[gtorich]

Thanks Brad.............got a email from Ramey at umi...........not much info except try different rotors. ???? Seems they are all the same from69-72 11 inch so i suppose i could try a different brand.

The other suggestion was to grind on the area where its hitting the rotor, no mention of how much to grind off..........could see this if these arms were only couple hundred bucks, but im having a few issues with wrecking $ 700 arms to just throw away if it doesnt work out.

Guess the question is about how much do you grind off, and about what is supposed to be a somewhat correct gap between the rotor and control arm.

Im going to get this right yet............of course with you guys helping . lol

Rich

[Sirrotica]

If it were me I would grind the A arm, put it back together and put a floor jack under the lower A frame with a chain around the axle of the floor jack, and over the top of the frame rail. This way you can compress the spring and watch the gap with it compressed. At full compression I would be comfortable with 1/8 inch, or .125 inches clearance.

I would do both sides with the jack and the wheel removed to affirm you had 1/8 inch under spring compression.

The only other way I could see to do this would be to have someone machine some spacers to go between the inner wheel bearing and the spindle to move the rotor and wheel bearing assembly outward.

Buying other brands of rotors would be iffy, because most rotors are made in china and probably at the same facility, no matter whose box they're in. To try the rotor, and return it would be iffy anyway if the store was paying attention that you put it together with wheel bearings, they might balk at taking it back. I guess it's nice to spend someone else's money when your product may be the problem.

Aftermarket manufacturers have a lot of latitude to point their problems at other sources, but that's what Hot Rodding is about, and has been since the aftermarket started building parts for cars. Making it all fit together and function is what we sign up for when we modify out cars. What they get for those lower control arms, I'd probably be upset too. Just like buying a set of headers and having to bash the tubes in for clearance when installing them, they aren't under $100 a set anymore.

[ZeGermanHam]

I disagree with the suggestions of grinding parts, or using spacers, etc. Between the interference occurring with the control arm and rotor, and the sway bar links and tie rods, there is clearly an issue with parts compatibility here. Grinding and spacing is not the way to go in my book, particularly since thousands of the UMI control arms have been sold and are highly regarded. You need to find which part(s) are wrong and replace them. Confirm the part numbers you ordered, and reference the numbers with what you physically received. I have the UMI upper & lower control arms, UMI sway bar and links, CPP brake & spindle kit, and Global West bump steer correction knuckle arms, and it all fits as it should. Don't go hacking things.

Generally speaking, experiences like this are why I typically prefer to buy parts in whole kits, rather than sourcing parts à la carte.

[Paul E]

Originally Posted by ZeGermanHam

I disagree with the suggestions of grinding parts, or using spacers, etc. Between the interference occurring with the control arm and rotor, and the sway bar links and tie rods, there is clearly an issue with parts compatibility here. Grinding and spacing is not the way to go in my book, particularly since thousands of the UMI control arms have been sold and are highly regarded. You need to find which part(s) are wrong and replace them. Confirm the part numbers you ordered, and reference the numbers with what you physically received. I have the UMI upper & lower control arms, UMI sway bar and links, CPP brake & spindle kit, and Global West bump steer correction knuckle arms, and it all fits as it should. Don't go hacking things.

Generally speaking, experiences like this are why I typically prefer to buy parts in whole kits, rather than sourcing parts à la carte.

This is EXCELLENT feedback and advice!

[Sirrotica]

Originally Posted by ZeGermanHam

I disagree with the suggestions of grinding parts, or using spacers, etc. Between the interference occurring with the control arm and rotor, and the sway bar links and tie rods, there is clearly an issue with parts compatibility here. Grinding and spacing is not the way to go in my book, particularly since thousands of the UMI control arms have been sold and are highly regarded. You need to find which part(s) are wrong and replace them. Confirm the part numbers you ordered, and reference the numbers with what you physically received. I have the UMI upper & lower control arms, UMI sway bar and links, CPP brake & spindle kit, and Global West bump steer correction knuckle arms, and it all fits as it should. Don't go hacking things.

Generally speaking, experiences like this are why I typically prefer to buy parts in whole kits, rather than sourcing parts à la carte.

Just a question here, the rep from UMI suggests that the OP grind his new parts, it wasn't my suggestion to find a work around. I originally said that the UMI part wasn't as it should be. The UMI rep must have already had an experience with parts not matching up because they commonly throw it off on, "We've never ever had a problem like yours before today", but they didn't tell the OP that. Is it a QC problem from UMI? The reply is that they've possibly run into this problem before.

Commonly one doesn't buy rotors to change their control arms, and UMI doesn't make rotors, they source them if they need to include them in a kit. It would have been nice if the representative told the OP who they suggest to buy from, rather than tell the OP to try different brands to solve his problem. He could have the choice of over 10 different vendors easily, which one should he pick? I was answering the question the OP asked about making the parts he currently has work, just to be clear. I've installed plenty of aftermarket parts that don't fit well together on my own, and customer cars, and have confronted problems just like the OP has, then was on my own to make the sum of parts work together. Just because you buy a kit from one manufacturer doesn't assure you that an install is going to be trouble free, been there done that.

So should the OP take all his parts off the car, and buy new UMI parts in a kit and start over? He's pretty committed to make what he has already purchased work for him, at least that was the impression I have.

[JLMounce]

I did receive your e-mail on this stuff Rich, but have been busy with family birthdays and anniversaries lately.

Have you by any chance taken a real close look to your upper control arm mounting brackets on the frame? If we assume for a second that there's nothing wrong with either your upper arms, or your lower arms and they are installed correctly, there's literally no way that +7 degrees of caster is your minimum caster setting. The SPC upper arms are designed to work with their lower arms which provide 2 degrees of positive caster in the arm. Mixed with the upper arm's 6 degree caster swing -3 to +3 degrees without effecting the ability to set camber properly, you can realistically get to around 5 degrees positive caster for a street alignment with minimal negative camber.

Ostensibly, any lower control arm that moves the lower ball joint would work alongside the SPC arm just as well.

What that means, is that assuming all the components were built and installed correctly, you would have close to 10 degrees of positive caster built in to the lower arm, which isn't correct. So, on the assumption that the arms were built correctly, the only way to achieve the alignment specs on your car is if the upper control arm mounts have been physically moved.

The repositioning of the top mount may also favor static negative camber settings without the use of large stacks of shims. All of these things could work together to reduce clearance from the lower control arm to the rotor.

Although it is uncommon due to how the A-body support stands are made for the upper control arm mount, a Guldstrand style modification is still technically possible on A bodie's, but requires that the entire mount be cut off the frame, the bottom of the mount trimmed and then repositioned and welded in place. It's nothing outside of the realm of possibilities for somebody that knows how they want their suspension setup and is a competent fabricator/welder.

I could see one control arm being made improperly in a jig, but both of your control arms made improperly and made improperly almost exactly even? That tells me there's something else going on here.

Edit: I went back and reviewed some of the photos you sent me with a finer tooth comb. It appears that you have the longer adjusting sleeves on the upper control arms in the forward position (towards the front of the car). Is this correct? If so, that's the reason you can get and lower on your caster angles. With the long adjuster sleeve in the forward position, about 3 degrees positive caster is the minimum you can get from the arm, add in the positive caster of the lower control arm and there you have it. Those might need to be reversed.

Reversing those sleeves and reducing the amount of caster will drop the steering arm relative to the lower control arm, increasing clearance for your sway bar which you've been struggling with.

[gtorich]

Jason, i see your a man of few words. lol...........not totally sure the umi lowers move the bj forward.........im getting more confused by the minute lately with this stuff.

Im just going by the instructions...........so am i reading these right or wrong.........with me im sure im leaning toward the wrong side. Pic enclosed

I'LL send you some better pics of the upper control arms mounting brackets.....

Im hoping im not driving you guys to drinking trying to figure out my blunders.......by the way im knocking off a few beers as we speak. lol

Rich

[gtorich]

maybe i should enclose this......

[gtorich]

So should the OP take all his parts off the car, and buy new UMI parts in a kit and start over? He's pretty committed to make what he has already purchased work for him, at least that was the impression I have.
__________________
Brad Yost

Brad you hit the nail on the head there...........To be clear Brad didnt say grind on the lower arm Raey at umi mentioned that, also buying different rotors..........well how many sets do you try to find out they are all the same..........with the upper and lower arms and everything else, i got about $1800 in this set up...........yeah, one way or the other these parts are gonna fit......

Got this from umi today..........way above my pay grade, also some pics on where i can grind on these arms.........but i see i have some other options before i do some surgery, so im gonna look into those....these are the "Brad Pitt" of rotors, so im thinking good to go. lol..........also some pics to show where to grind the arms.

As per Jason...........Maybe i have these uppers arms on wrong..........but the instructions say otherwise.........will look into it further.

Thanks for helping guys...........oh boy, you can see i need it.

Rich