New and Improved Upper A Arms with Ball Joint
10-30-2009 | 04:39 PM
#1
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Joined: Dec 2001
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From: Horicon, WI
New and Improved Upper A Arms with Ball Joint
On 05/03/2007 I posted this thread:
https://rennlist.com/forums/928-foru...del-928-a.html
We had just developed replacement steel upper a-arms for late-model 928's that used a heim-style rod end instead of the ball joint.
Now we have improved on our original design, and include a rebuildable and serviceable ball joint. The bear was finding time and money to have the pintel of the ball joint custom made for us in the proper metric taper for the 928 so this could happen.
The finished product is very nice, and I have already installed them. The car got into alignement spec right away, and the drive is fanatstic. Like all of our steel upper a-arms, the camber is held very accurately and smoothly throughout the arc of suspension travel, unlike the OEM rubber upper a arms.
We were able to hold the price on these new and improved upper a-arms the same. No price change since 2007!
Our webpage on this item is here: http://www.928motorsports.com/parts/...eplacement.php
At the moment I have 3 pair in stock, and we'll make more.
Price is per PAIR.
https://rennlist.com/forums/928-foru...del-928-a.html
We had just developed replacement steel upper a-arms for late-model 928's that used a heim-style rod end instead of the ball joint.
Now we have improved on our original design, and include a rebuildable and serviceable ball joint. The bear was finding time and money to have the pintel of the ball joint custom made for us in the proper metric taper for the 928 so this could happen.
The finished product is very nice, and I have already installed them. The car got into alignement spec right away, and the drive is fanatstic. Like all of our steel upper a-arms, the camber is held very accurately and smoothly throughout the arc of suspension travel, unlike the OEM rubber upper a arms.
We were able to hold the price on these new and improved upper a-arms the same. No price change since 2007!
Our webpage on this item is here: http://www.928motorsports.com/parts/...eplacement.php
At the moment I have 3 pair in stock, and we'll make more.
Price is per PAIR.
10-30-2009 | 06:17 PM
#4
Rennlist Member
Joined: Aug 2003
Posts: 2,624
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From: Indianapolis
Those look pretty stunning Carl. I like the grease fitting in the top, definately a nice touch. Are these units completely sealed, or are they open on the bottom? In either case, with that zerk on the top, "cleaning" these out will be a snap. Dont sell yourself short Carl, you didnt mention the added zerks on the pivot bearings too. What are the specs on those bushings, did they improve any too?
10-30-2009 | 06:51 PM
#5
Nordschleife Master
Joined: Apr 2003
Posts: 9,600
Likes: 34
From: Abbotsford B.C.
The origonal arms had grease nipples on the inner joints too Hans.
Carl,
The new insert looks great! Is the threaded portion a custom thread or is it possible to just machine out the origonal piece, tap it and install these? Even though this joint on the origonal version had zero problems.
The other question I have is if you have redesigned these arms dimensions. Everyone that I have seen install these, and those of them that I have had to install have required around 4mm of shimming in order to get the alignment set even close to stock. Prior to the 4mm of shimming 2-2.5 deg of negative camber was the minimum achievable. I ended up replacing the studs with bolts (grade 10.9 70mm long) and put the bolts through from the engine bay. I then used the nut on the outside in the fenderwell. A few quick zaps with the impact gun and I can get the nut tight without having to put a wrench inside. After there is some pressure on the nut one can put a torque wrench on the outside and torque to specs. This made doing the shims much easier as it was a bunch of trial and error as I didnt feel like doing all the math to calculate the required shim. Plus this way I can now easily change the shims to get the camber to anything I want.
But just to ask it once more. Has the centerline of the replacement joint to the edge of the pivot bar which bolts to the car been changed from the origonal design?
Carl,
The new insert looks great! Is the threaded portion a custom thread or is it possible to just machine out the origonal piece, tap it and install these? Even though this joint on the origonal version had zero problems.
The other question I have is if you have redesigned these arms dimensions. Everyone that I have seen install these, and those of them that I have had to install have required around 4mm of shimming in order to get the alignment set even close to stock. Prior to the 4mm of shimming 2-2.5 deg of negative camber was the minimum achievable. I ended up replacing the studs with bolts (grade 10.9 70mm long) and put the bolts through from the engine bay. I then used the nut on the outside in the fenderwell. A few quick zaps with the impact gun and I can get the nut tight without having to put a wrench inside. After there is some pressure on the nut one can put a torque wrench on the outside and torque to specs. This made doing the shims much easier as it was a bunch of trial and error as I didnt feel like doing all the math to calculate the required shim. Plus this way I can now easily change the shims to get the camber to anything I want.
But just to ask it once more. Has the centerline of the replacement joint to the edge of the pivot bar which bolts to the car been changed from the origonal design?
10-30-2009 | 08:02 PM
#6
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Joined: Dec 2001
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From: Horicon, WI
Hans - they are "open" on the bottom into the silicone cup.... so they are not "open" as in debris will get in there... the silicone cup controls splash and spray. But they are "open" such that when the grease is applied at the zirk at the top, the old grease is forced out thru the bottom. This is by design.
Colin - yes, we took our manufacturing jig to task to make sure that the length of the arms were right and the ball joint would locate the spindle in the right place. It must have worked because on my own car, where the camber eccentric was all the way out to get the camber setting I wanted, now the camber eccentric is in the center of its range of adjustment, and the camber is set to factory spec. Also, we found the L and R side arms came in to matching camber settings more easily.
Colin - yes, we took our manufacturing jig to task to make sure that the length of the arms were right and the ball joint would locate the spindle in the right place. It must have worked because on my own car, where the camber eccentric was all the way out to get the camber setting I wanted, now the camber eccentric is in the center of its range of adjustment, and the camber is set to factory spec. Also, we found the L and R side arms came in to matching camber settings more easily.
10-30-2009 | 08:06 PM
#7
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Joined: Dec 2001
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From: Horicon, WI
Colin - I just saw your other question... no, you cannot install this new ball joint in the aperture of the old ball joint. Its too big. To remanufacture the old ones, we have to cut the old end off and weld on the new ball joint carrier.
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10-31-2009 | 03:05 AM
#8
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Joined: Jun 2006
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From: ɹəpun uʍop 'ʎəupʎs
Nice product.. definitely one for the list of future modifications.
Is the 1.2lbs of weight saving per side quoted on the web page for these newer Mark II arms? Or is that left over from the first version of the page?
Is the 1.2lbs of weight saving per side quoted on the web page for these newer Mark II arms? Or is that left over from the first version of the page?
10-31-2009 | 10:41 AM
#9
Nordschleife Master
Joined: Apr 2003
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From: Abbotsford B.C.
That you for the clear and concise answers Carl.
The one other question that I do have regarding these is, do you recommend using any red (or other) Loctite on the threads which hold the ball joint into the housing to prevent it backing out (highly unlikely that it would)?
The one other question that I do have regarding these is, do you recommend using any red (or other) Loctite on the threads which hold the ball joint into the housing to prevent it backing out (highly unlikely that it would)?
11-01-2009 | 11:20 AM
#10
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From: Horicon, WI
Colin - Loctite red is a favorite of mine on critical parts (and this would be one) IF you can get at the part with a torch to heat it for loosening. If not, then use Loctite blue (no heat required for disassembly).
As it is, we ship the a-arms with the ball joint already installed and torqued for you.
Hilton - they came in within a tenth of a pound of being the same weight as before. Only a very little heavier, so now the weight savings is like 1.1 pounds per side.
As it is, we ship the a-arms with the ball joint already installed and torqued for you.
Hilton - they came in within a tenth of a pound of being the same weight as before. Only a very little heavier, so now the weight savings is like 1.1 pounds per side.
11-02-2009 | 01:13 AM
#13
Racer
Joined: Dec 2006
Posts: 454
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From: SAN DIEGO
NEW A ARM
Hello Carl i have your version steel before the new improved-How would the old version hold out versed the new one.I have not installed them yet-i just bought 86-95 A steel version through a member whom inturn bought from you guys.Upgraded cost 285.00?
11-02-2009 | 11:49 AM
#15
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From: Horicon, WI
Red Shark: If the first design is cared for correctly, they will last a long long time. However, this design is better for dirty locations because it is sealed up better, and more easily serviced.