NewZed Posted July 28, 2015 Share Posted July 28, 2015 I heard this a long time ago. . . "If it breaks, make it stronger. If it doesn't break, make it lighter." Nietzsche's unquoted works.... Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted July 28, 2015 Share Posted July 28, 2015 What do the fasteners that attached that to the LCA look like? Did the rear bolt and washer bend? Can you post a picture? Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 28, 2015 Author Share Posted July 28, 2015 (edited) The bolts are all perfect. The washer on the rear hole is bent. I think you are spot on about the need for more meat around the bolt hole. I'm waiting on a quote from an on-line supplier for both 4130 and 4140HT. My only real remaining question is on the clevis bending. Chicken or egg? My best pics are two quotes up. Edited July 28, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 28, 2015 Author Share Posted July 28, 2015 Just ordered a 6"X12" piece of 3/8" 4130 sheet from AEDMotorsport.com. $130! Dang, that's half of the TTT kit. If I was in a hurry (and if I run into any snags), I will sure give the TTT kit a try. If anybody finds any 5/8-18 RH inner tie rod ends, give me a yell-I'd love to have longer swaged tubes made up to reduce exposed threads on my barrels. Quote Link to comment Share on other sites More sharing options...
beermanpete Posted July 29, 2015 Share Posted July 29, 2015 Perhaps rather than simply making the bracket thicker and/or wider side rails could be incorporated to stiffen it without adding a lot of extra weight? Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 29, 2015 Author Share Posted July 29, 2015 (edited) Pete-I tossed that idea around but I don't know that much about fabricating and metallurgy. Can welding ever weaken a part by jacking up the heat treating?? That's why I just bought the CM. plus, it's kinda crowded in there with the sway bar and stuff. Edited July 29, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
beermanpete Posted July 29, 2015 Share Posted July 29, 2015 Pete-I tossed that idea around but I don't know that much about fabricating and metallurgy. Can welding ever weaken a part by jacking up the heat treating?? That's why I just bought the CM. plus, it's kinda rowdies in there with the sway bar and stuff. Yes, welding can cause problems with strength if it is not done correctly. For this a good welder should be able to do it ok. Another option would be to start with a thicker piece of steel and machine the center thinner, leaving ribs at the edges. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted August 22, 2015 Author Share Posted August 22, 2015 (edited) Ok guys. I have all my parts on-hand to put this back together. I called azcarbum@gmail.com who sold me this kit in order to see what failures and failure modes have been reported. He said the only failures that have been reported have been in either wrecks or off-track excursions. He also said he chose the 5/8" clevis so that it would be the point of failure instead of the TC box in the frame. So, for now I have tabled the idea of beefing the system up. I do plan to use his longer tubes to allow for more thread engagement. If I shorten the dogleg a bit, the longer rod should work-it was just millimeters too long when I first assembled all this. But, I have another question for the suspension committee: should I reassemble with the ball joint bolted to the BOTTOM of the TTT control arm, or should I cut a window in the box section of the control arm so that I can mount the dogleg to the BOTTOM of the LCA and mount the ball joint ON TOP? Seems to me that mounting it this new way will reduce "bump steer" some and reduce the moment on the TC rod. I seek your suggestions/discussion while I get on the drill press and start making dog legs from 4130 per 74_'s design. Edited August 22, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
beermanpete Posted August 23, 2015 Share Posted August 23, 2015 I think moving the ball joint will effect the roll center, not bump steer. If it is enough to be usefull I don't know. Quote Link to comment Share on other sites More sharing options...
beermanpete Posted August 23, 2015 Share Posted August 23, 2015 I think moving the ball joint will effect the roll center, not bump steer. If it is enough to be usefull I don't know. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted August 23, 2015 Author Share Posted August 23, 2015 (edited) I understand the whole bumpsteer/roll center thing, that's why I put the quotations on "bump steer". But it's a good thing to get that outboard end of the LCA as low as the wheels will allow, isn't it? (Text sent in a discussion tone, not an exasperated tone). I may just have to mock it up and see how the different configurations affect the dynamic toe. Sure wish my new garage was finished. It just won't stop raining here long enough to get any concrete work done and all I lack is a driveway. Working all crammed in next to the minivan is a real buzz-kill. Edited August 23, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted August 23, 2015 Share Posted August 23, 2015 Both configurations will be equivalent as far as bump steer, roll center and camber gain are concerned. For kinematics, all that matters is the distance between the centers of the suspension attach points. The different configurations will cause different bending moments on the dog-bone. However, with the use of the improved dogleg, I don't think you will have a problem in either configuration. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted August 23, 2015 Author Share Posted August 23, 2015 (edited) So it doesn't matter what happens between the inner pivot and the ball joint, I get it. Changing the angle on the LCA doesnt accomplish a thing of the location of the ball joint and inner pivot don't change. Got it. Thanks! This winter when I replace the tie rods I plan to move those inner pivot points up. Edited August 23, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted August 24, 2015 Share Posted August 24, 2015 (edited) I would look at the specs on whatever clevis you use. I think just like rod ends there are several different grades (strengths). If it's supplied without specs then that's questionable. +1 on the 4040 Edited August 24, 2015 by Chris Duncan Quote Link to comment Share on other sites More sharing options...
heavy85 Posted August 26, 2015 Share Posted August 26, 2015 I added caster by adding shims between the end of the step in the TC rod and the theads to add 1-2 deg of caster. 2 was too much and kept spinning in slow, heavy braking turns so back to one. There is enough slop in the factory TC mount to the control arm there is no bind. The inner control arm has a spherical too. The TC bushing is Gman nylon cone style with factory rubber on the back side. One of next mods is to change the mount out for likely one of those ball cup style (repurposed tie rods). Cameron Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted August 31, 2015 Author Share Posted August 31, 2015 (edited) Finally starting to move on this. Thinking about having the dogleg plasma cut. Does plasma cutting mess up the metallurgy of 4130? Edited August 31, 2015 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted August 31, 2015 Share Posted August 31, 2015 I would have them water jetted or cut out on a mill. If you do have them plasma cut, then make sure you clean up the edges. The plasma cut can leave a rough edge that can create stress risers. Quote Link to comment Share on other sites More sharing options...
rjracin240 Posted September 7, 2015 Share Posted September 7, 2015 That is definitely the preferred failure mode. Years ago, I had one fail by fracture (different set-up than I am currently running). Not a pretty thing. You can see the bent TC tube on the ground in front of the car. It had fractured in the threaded portion adjacent to the attachment at the LCA. Remember it well! Quote Link to comment Share on other sites More sharing options...
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