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Discussion Starter · #1 ·
I was trying to install the drivers side upper control arm on my Cobra, the back threaded shaft is hitting the brace so not allowing me to install the nut. I was thinking about making a plate and drilling matching mounting holes to bring the control arm out away from the brace. Anyone have this issue or better solution. Here is a picture.
Thanks
 

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Discussion Starter · #4 ·
Rich
The shaft hits the brace first and the nut makes it worse even after installed and tighten down. In fact the picture doesn't show it but the upper control arm isn't even contacting the frame in the picture..
Thanks.
 

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FFCobra Craftsman
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There was a thread on this a month or two ago on the other forum. My recommendation was a spacer made from 1/4 or 3/8 steel flat stock that is full width so there are two holes in it to space the UCA away from the frame just enough for clearance.
 

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I was trying to install the drivers side upper control arm on my Cobra, the back threaded shaft is hitting the brace so not allowing me to install the nut. I was thinking about making a plate and drilling matching mounting holes to bring the control arm out away from the brace. Anyone have this issue or better solution. Here is a picture.
Thanks
Do not do this. That will change your suspension geometry, and weird things will happen.

Cut out a 4-6" section of the brace, and then weld/bolt a new section around that. Kind of like installing a power brake booster.
 

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Discussion Starter · #9 ·
I did send a message and picture to FF today put didn't hear back yet, I do have a Mig and Tig welder, I may cut the square tube brace off move it in and weld it so not to change the geometry. I did remember a forum conversation on this also but can't seem to find it.
Dan
 

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On a Mk4 the upper control arm should be mounted on the side of the mount and not on the top as in the Mk3. I just looked at my car and the passenger side is closer to the frame than the drivers side. I don't think the nut would come off the passenger side without removing the arm. However, it is not as close as yours.

My question would be: was the mount welded to the frame a bit too far back or were the holes drilled too far back. Thinking about this the holes are probably already in the mount when welded to the frame.

If I am speculating correctly, that the mount is a bit too far back, and it stays that way, I would question if the proper geometry (caster in this case) could be corrected with adjustment in the swing arms. That is also assuming you make the correction Bob Cowan makes by cutting the 3/4" tubing out of the way and reinforcing it from behind. Also mounting the arm with the nut already installed would help after this change.

Now, as I'm looking at my pictures, that mount could be mounted too much toward the center of the car bringing the arm closer to the frame?? In this case you could space it away from the mount at bit. This would affect the camber adjustment. I don't think either the camber or caster will be changed that much but maybe Bob Cowan could comment again on that as he has a good understanding of the alignment on these cars.

Have FFR check their jigs for mounting and welding of this piece and that the placement of the holes in the mount are being done correctly. Maybe the piece is being put on backwards or on the wrong side?? The more I think about this the more variables that FFR may not be controlling with their jig. Refer FFR to this thread and ask them for a recommendation.

A lot of the guys from FFR are away this week. Call them next week after emailing again. A phone call will get you better attention than emails alone.

Here are pictures from my car, mine was the 1st Mk4 to leave FFR:

Passenger side:


Not enough room to get nut off but room to mount arm


Drivers side has much more room


George
 

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It's not incorrectly welded mounts or improper installation---FFR has recently changed upper control arm suppliers and the new ones fit like the proverbial saddle on a hog. Look at the photos that the original poster included and compare those with George's and you'll see the difference. In addition to the interference with the chassis from the crossbar nut the ball joint mounting plate is no longer unidirectional so builders are finding it impossible to mount the solid link forward on both sides as is recommended. The issues have been discussed several times on the other forum; as far as I know there has been little or no response from FFR.

On a Mk4 the upper control arm should be mounted on the side of the mount and not on the top as in the Mk3...
Not necessarially correct. Whether to use the top horizontal mounts or the vertical side mounts is dictated by which spindles are used. Fox and SN95 spindles without a SAI correction mount into the the top set and FFR proprietary spindles or SN95s with SAI mod use the sides.

Jeff
 

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I agree with Craig, make a spacer (actually 2 spacers, 1 for each side of the car). I sure wouldn't want to cut my new powder-coated frame to fix an interference caused by a miss in the design. If you put it together with spacers on both sides 1) it shouldn't cause any problems with steering (if anything I think it would have more negative camber gain on suspension travel, not a bad thing) and 2) it can easily be undone when FFR has a fix for this oversight.
 

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If you space the arm out away from the frame, you're making the arm shorter. That means as the suspension works, it will move through a greater arc. The arc of the upper and lower arms is different on purpose. That intentionally changes camber through the range. A shorter arm will increase camber change, and a longer arm will decrease.

Since the tie rod end is attached closer to the lower arm, you'll also increase bump steer.

I have a MII. The upper arm mount has two holes - one for standard width, and one for pin drive. One day I decided to mount the arm in the pin drive holes, just to see what would happen. By my rough calculations, it should have lowered the roll center a little bit. But it increased bump steer a lot, so I changed it back.

Suspension pick up points play a gigantic role in how the car handles and drives. Companies like FFR spend thousands of dollars in computer software and hundreds of hours in computer modeling to get it just right. I think they've done a pretty good job. Unless you're willing to spend the time and money to redesign the whole suspension, I would not recommend changing a single pick up point.
 

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Bob, it's only a 1/4 inch movement. The UCA wil get shortened by the same 1/4 inch to maintain any given camber setting. W/ all the options of inner mount positions,Fox or SN95 or FFR spindles,Sn95 w/ or w/o SAI mod, I don't think 1/4 inch is going to be a problem.
 

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FFR has recently changed upper control arm suppliers and the new ones fit like the proverbial saddle on a hog.
The issues have been discussed several times on the other forum; as far as I know there has been little or no response from FFR.
That's not good:confused1:..FFR should try to jump on these type of issues, and correct them ASAP. This is an area that a builder should not have to start modifying, simply because FFR changed a part. :(

I really hope that FFR doesn't lose focus, just because of the 818..
 

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SPC Performance is the supplier of the old control arms. I would source a set of arms that fit before I starting cutting up my frame. You should be able to e-bay the old arms, or return them to FFR once they figure this out. FFR will have to address this sooner or later. Dumb mistakes like this happen, but they require a quick response. You would think the shock problem from several years ago would have left an impression.

All that talk about computer design and six sigma goes out the window when we see stuff like this.
 

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Bob, it's only a 1/4 inch movement. The UCA wil get shortened by the same 1/4 inch to maintain any given camber setting. W/ all the options of inner mount positions,Fox or SN95 or FFR spindles,Sn95 w/ or w/o SAI mod, I don't think 1/4 inch is going to be a problem.
Yes, it's only 1/4-1/2" difference. But it matters. The difference between pin drive and standard isn't much either, but it sure made a difference - and not in a good way.

Shortening the upper arm doesn't compensate for the change. By doing that, you'll increase the camber change and bump steer through suspension motion.

Think about doing a front end alignment. Making a change of 0.5* camber or 1/16" toe makes a huge difference in the way the car handles and rides. Those are tiny changes that make big differences.

Sit down with a piece of paper and a pencil. Draw it out as it is now, and with the mounting point moved laterally. Then see what happens as you move the suspension through it's range of motion.

The only way to use a spacer and still maintain the same relationship is to also move the lower arm pick up points out by the same amount. You'd also have to move the shock mount and sway bar mount out or you would change the wheel rate. Don't forget to lengthen the steering rack, too.
 

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Bob is correct: Moving the mounting points by shimmng the mount outward is the last thing you should do, as stated above camber gain and bumpsteer problems could result. I bought my Coupe kit back in 03 and the control arms were pole position Mustang items that have the greese fitting on the end. The ends are a bit shorter then what you pictures are showing and look like they should work fr you The easy fix might just might be changing the upper control arms. I do agree FFR needs to be responsible and fix this interference problem, or compensate you for the added cost. You should not have to cut and weld in an offset to clear an item that is supposed to fit.
Call them on the phone, e-mail in my experience does not get much of a response. If neither works send them a registured letter that someone has to sign to accept, that way you will know who to talk to when you call back.
HTH
CB
 

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Discussion Starter · #20 ·
I didn't think this post would cause this much conversation. I'm still thinking about cutting the 3/4 inch square tube off at the mounting point and moving it in then Tig weld it back to the vertical post. The passenger side doesn't have a clearance problem and it looks like the brace is welded in farther than the drivers side. Does anyone else the new style upper control arm have a clearance problem, maybe my drivers side brace was missed welded.
Dan
 
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