SFR control arms
#1
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SFR control arms
SFR will now be offering chrome-moly control arms for the 944 and 968s!
http://boards.rennlist.com/upload/controlarms01.jpg
http://boards.rennlist.com/upload/controlarms02.jpg
They are made out of .120 wall ODM. They are TIG welded and feature a replacable teflon lined (prevents squeaking) 3/4" heim joint to replace the stock ball joint. The heim joint allows much more travel before it binds up like the stock one would. The stock rubber bushings have been replaced with Delrin bushings. You continue to use the same castor block but we will be offering billet units in the near future (as an option). The control arms will be powder coated black but other colors can be custom ordered.
We are going to price these at $1099 a set. These are the perfect alternative to the factory units for street and track cars;^)
http://boards.rennlist.com/upload/controlarms01.jpg
http://boards.rennlist.com/upload/controlarms02.jpg
They are made out of .120 wall ODM. They are TIG welded and feature a replacable teflon lined (prevents squeaking) 3/4" heim joint to replace the stock ball joint. The heim joint allows much more travel before it binds up like the stock one would. The stock rubber bushings have been replaced with Delrin bushings. You continue to use the same castor block but we will be offering billet units in the near future (as an option). The control arms will be powder coated black but other colors can be custom ordered.
We are going to price these at $1099 a set. These are the perfect alternative to the factory units for street and track cars;^)
Last edited by TurboTim; 08-30-2003 at 09:56 PM.
#2
Out of curiousity, what kind of load testing have you done on these? I would guess you have run them on your car and they are holding up fine, but have you done any sort of static load to determine its failure point?
I am continually impressed at the quality of your fab work. Its a shame no one makes clear body panels so that they don't cover your work up! lol
Regards,
I am continually impressed at the quality of your fab work. Its a shame no one makes clear body panels so that they don't cover your work up! lol
Regards,
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I had a few people ask how the arms attach to the spindle so I thought I would address that.There is a machined bolt that slides through the heim joint that allows the arm to bolt to the spindle.
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[QUOTE]Originally posted by sh944
[B]Out of curiousity, what kind of load testing have you done on these? I would guess you have run them on your car and they are holding up fine, but have you done any sort of static load to determine its failure point?
I have been in contact with one of our members who works at a place where they can x-ray the arms as well as test the strength of the arms.
[B]Out of curiousity, what kind of load testing have you done on these? I would guess you have run them on your car and they are holding up fine, but have you done any sort of static load to determine its failure point?
I have been in contact with one of our members who works at a place where they can x-ray the arms as well as test the strength of the arms.
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#8
Drifting
Tim,
The arms look good. What is the mechanims for attaching the front sway bar. I assume you wouldn't use the stock style rubber bushings, but you would ned some sort of spacers.
The arms look good. What is the mechanims for attaching the front sway bar. I assume you wouldn't use the stock style rubber bushings, but you would ned some sort of spacers.
#10
Instructor
One remarque: I don't think that people in Switzerland could pass Swiss TÜV with a part like this that is obiously not original. For example you have no chance without a bunch of papers (for example: Paperwork from a Swiss car import firm) to pass Swiss TÜV with cross drilled on any 944 because they didn't have orginally. How about this in the U.S.?
kind regards Frank
kind regards Frank
#11
Tim,
Make a pair of these out of mild steel, and I'd buy a pair in a heartbeat. I don't want to pay more than 500 though. If you use sperical bearings, be sure to make dust caps available too.
I don't want chrome moly because:
Needs to be heat treated after being welded.
Tends to break at weld joints.
Cracks/Breaks when pushed beyond yield strength.
Need to be tig welded.
Provides more strength than the application needs.
I want Mild steel because:
Bends when overstressed - doesn't break.
Strong.
will not break at welds joints.
Welds easily with a mig welder.
Cheap!
I've attached a pic of mild steel a-arms for your reference. theres a few thousand of these running around the streets. These are $439.95 a pair.
Sean
Make a pair of these out of mild steel, and I'd buy a pair in a heartbeat. I don't want to pay more than 500 though. If you use sperical bearings, be sure to make dust caps available too.
I don't want chrome moly because:
Needs to be heat treated after being welded.
Tends to break at weld joints.
Cracks/Breaks when pushed beyond yield strength.
Need to be tig welded.
Provides more strength than the application needs.
I want Mild steel because:
Bends when overstressed - doesn't break.
Strong.
will not break at welds joints.
Welds easily with a mig welder.
Cheap!
I've attached a pic of mild steel a-arms for your reference. theres a few thousand of these running around the streets. These are $439.95 a pair.
Sean
#12
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Those rod ends are pretty beefy, but they are still going to snap off at the jam nut from fatigue. The teflon in the rod end is going to beat out and/or melt from the brake disc heat.
I can't see from the picture, but the hole for the bar mount needs to have a sleeve in it so the tubing doesn't squeeze down when the bolt is over tightened. It would be nice to have some flat surface for the sway bar mounts/bushings to bear against.
The bar hole should have some reinforcement on it too, so it won't crack there. Of course the rod end is going to break off long before that happens.
The curve in the tubing at the caster mount is a major detriment to stiffness, except for the guy who wants the arms made of mild steel. He doesn't need stiff control arms.
Using a machined bolt for a pin is not good. It needs to be 4340 or 300M and it needs to designed, machined, and heat treated just right. It would be nice to enlarge the pin to 19mm if possible.
I can't see from the picture, but the hole for the bar mount needs to have a sleeve in it so the tubing doesn't squeeze down when the bolt is over tightened. It would be nice to have some flat surface for the sway bar mounts/bushings to bear against.
The bar hole should have some reinforcement on it too, so it won't crack there. Of course the rod end is going to break off long before that happens.
The curve in the tubing at the caster mount is a major detriment to stiffness, except for the guy who wants the arms made of mild steel. He doesn't need stiff control arms.
Using a machined bolt for a pin is not good. It needs to be 4340 or 300M and it needs to designed, machined, and heat treated just right. It would be nice to enlarge the pin to 19mm if possible.
#13
Nordschleife Master
Originally posted by Chris Cervelli
The curve in the tubing at the caster mount is a major detriment to stiffness, except for the guy who wants the arms made of mild steel. He doesn't need stiff control arms.
The curve in the tubing at the caster mount is a major detriment to stiffness, except for the guy who wants the arms made of mild steel. He doesn't need stiff control arms.
My Fabcar arms are mild steel. They appear to be one of the most popular choices among racers. Are you telling me that all the racers using fabcar arms don't need stiff control arms, or are you only referring to mild steel in the tube design?
Those look WAY too weak!
#14
Nordschleife Master
Originally posted by turbinek
One remarque: I don't think that people in Switzerland could pass Swiss TÜV with a part like this that is obiously not original. For example you have no chance without a bunch of papers (for example: Paperwork from a Swiss car import firm) to pass Swiss TÜV with cross drilled on any 944 because they didn't have orginally. How about this in the U.S.?
kind regards Frank
One remarque: I don't think that people in Switzerland could pass Swiss TÜV with a part like this that is obiously not original. For example you have no chance without a bunch of papers (for example: Paperwork from a Swiss car import firm) to pass Swiss TÜV with cross drilled on any 944 because they didn't have orginally. How about this in the U.S.?
kind regards Frank
In California, there is something similar to the system in Switzerland for engine modifications.
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Right. The Fabcars are not tubular construction. The cross section is a large rectangle and the sway bar mounts stiffens that additionally.
Even so, I doubt they are as stiff as a Charlie arm. It is probably academic however, since both arms are considerably stiffer (and stronger) than the chassis they attach to.
I think the Fabcar arms are super nice, but the Charlie arm is a better value. Plus you get the enlarged pin, which is the critical part of the whole thing.
I guess you could make mild steel arms stiff enough if the tubing diameter was large enough. The arm is tough to design since you can't properly triangulate and keep tire clearance.
Even so, I doubt they are as stiff as a Charlie arm. It is probably academic however, since both arms are considerably stiffer (and stronger) than the chassis they attach to.
I think the Fabcar arms are super nice, but the Charlie arm is a better value. Plus you get the enlarged pin, which is the critical part of the whole thing.
I guess you could make mild steel arms stiff enough if the tubing diameter was large enough. The arm is tough to design since you can't properly triangulate and keep tire clearance.