Trailing Arm Bushings, What material to select? |
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Trailing Arm Bushings, What material to select? |
malcolm2 |
Aug 28 2014, 03:32 PM
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#1
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I need to replace the rear wheel bearings, so "while I am in there" I will also tackle the bushings.
Rubber looks to be the OEM choice but is hard to find with the exception of the elephant racing kit that includes the shafts and install tools. $300+ I used the Elephant bushings on the front. I found poly-graphite to be the least expensive < $20 for a set of 4 bushings only With Delrin as the middle of the road choice. @ $50 for a set of 4 bushings only So what is the +/- of each material? Can you throw a few vendors out there? My car is a daily driver? Clark |
malcolm2 |
Sep 17 2014, 06:08 PM
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#2
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
The phone just rang, Jonathon says the answer is JB WELD. They say they have done hundreds like that.
But still no written instructions. (IMG:style_emoticons/default/mad.gif) I have some time while I wait on Bruce's carton and my new pivot arms, so maybe they will have some explicit instructions by the time it arrives. Lots of good things said about Rebel Racing, but this JB weld thing seems half-assed to me. Internet research to come on that stuff, I guess. I guess if I follow thru with the install, I'll video the whole thing and they (OR the 914World) can have it from YouTube. shouldn't I get a discount? (IMG:style_emoticons/default/piratenanner.gif) |
JamesM |
Sep 17 2014, 10:52 PM
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#3
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Senior Member Group: Members Posts: 1,915 Joined: 6-April 06 From: Kearns, UT Member No.: 5,834 Region Association: Intermountain Region |
When I got my rebel setup for the fronts I was feeling the same way about the jb weld, but trust me, it is the way to go. The issue is that the factory parts were not precise and the rubber bushings just took up the slop, when you are working with a non compressible material there is no way you can ensure a perfect fit on every car. On the fronts anyway the JB weld acted as a sort of filler between the sloppy control arm manufacturing and the precision machined race for the bushing. once together it is very clean.
You can see my install of the fronts here. http://www.914world.com/bbs2/index.php?sho...211241&st=0 I am a little suspect of the shaft fit on the rear though, I thought they were going to provide new shafts machined to fit their bushings. as with the fronts the PTFE slides against a precision machined race, by the looks of the rear i would think it is intended to spin around a precision machined shaft to match (unless the PTFE spins inside that steel tube in which case you probably fasten the tube itself to the swing arm, and the PTFE inserts to the shaft). Do the PTFE inserts spin in the tube or are they interference fit in? Do you have pics of the shims for the thrust surfaces? That is the area I am most curious about. The phone just rang, Jonathon says the answer is JB WELD. They say they have done hundreds like that. But still no written instructions. (IMG:style_emoticons/default/mad.gif) I have some time while I wait on Bruce's carton and my new pivot arms, so maybe they will have some explicit instructions by the time it arrives. Lots of good things said about Rebel Racing, but this JB weld thing seems half-assed to me. Internet research to come on that stuff, I guess. I guess if I follow thru with the install, I'll video the whole thing and they (OR the 914World) can have it from YouTube. shouldn't I get a discount? (IMG:style_emoticons/default/piratenanner.gif) |
malcolm2 |
Sep 18 2014, 12:03 PM
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#4
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
Do the PTFE inserts spin in the tube or are they interference fit in? Do you have pics of the shims for the thrust surfaces? That is the area I am most curious about. The PTFE inserts appear to be tight, I'll check that and also get a picture of the shim later today. Below, I drew up a ruff idea of how Jonathon explained the install process to me. 2ndly I mentioned to him that the 2nd rebel assembly (not in the video) slipped in the top of the OEM arm but was very tight at the other end. He said, "no worries. Just add the JB WELD, then press the rebel assembly in, if needed." Clark |
ChrisFoley |
Sep 18 2014, 12:56 PM
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#5
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I am Tangerine Racing Group: Members Posts: 7,934 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
2ndly I mentioned to him that the 2nd rebel assembly (not in the video) slipped in the top of the OEM arm but was very tight at the other end. He said, "no worries. Just add the JB WELD, then press the rebel assembly in, if needed." I don't like that at all. The welded end of the trailing arms is significantly out of round which will tend to squish the sleeve somewhat, making the bushing out of round. I provide a sanding drum in my kits to prep inside the welded end - so the sleeve can be installed without causing deformation. |
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