Strut Rod FIX

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   It is interesting that some race cars use strut-type front lower control arms. The control arm typically has a spherical joint at the chassis pivot, a ball-joint for the steering knuckle, a clevis for the strut-rod attachment to the arm and a heim with threaded adjuster for the strut rod attachment to the chassis.   So more range of adjustment and movement possible than with rubber bushings, but a very similar concept to the stock arrangement that seems to work well on the track.  
One thing that helps minimize pre-load on the strut-rod and bushing of the stock assembly is to slightly loosen the bolts between strut rod and control arm when adjusting caster, to allow the rod to align itself to the arm, then torque the bolts once adjusted. Slotting the holes may help if pushing limits of caster adjustment.  

Hope this helps,RD

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Red Devil Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/10/2007 Location: Canada Status: Offline Points: 1743	Post Options Post Reply Quote Red Devil Report Post Thanks(0) Quote Reply Posted: Oct/28/2017 at 4:38pm
	It is interesting that some race cars use strut-type front lower control arms. The control arm typically has a spherical joint at the chassis pivot, a ball-joint for the steering knuckle, a clevis for the strut-rod attachment to the arm and a heim with threaded adjuster for the strut rod attachment to the chassis. So more range of adjustment and movement possible than with rubber bushings, but a very similar concept to the stock arrangement that seems to work well on the track. One thing that helps minimize pre-load on the strut-rod and bushing of the stock assembly is to slightly loosen the bolts between strut rod and control arm when adjusting caster, to allow the rod to align itself to the arm, then torque the bolts once adjusted. Slotting the holes may help if pushing limits of caster adjustment. Hope this helps,RD

Mopar_guy Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4823	Post Options Post Reply Quote Mopar_guy Report Post Thanks(0) Quote Reply Posted: Oct/28/2017 at 7:57pm
	My initial thought looking at the Cougar setup is the bushing might not last long. Fords have the rods going forward rather than to the rear and I'm thinking the loading is more severe to the rear. Maybe I'm wrong but that's how I perceive it.
	"Hemilina" My 1973, 5.7 Hemi swapped Javelin

Greyhounds_AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Nov/14/2009 Location: Kansas City Status: Offline Points: 1268	Post Options Post Reply Quote Greyhounds_AMX Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 11:27am
	That's a good point - the Ford setup is in tension most of the time. That could play into whether it'd be workable on our cars.
	1968 AMX 390 w/T5

Greyhounds_AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Nov/14/2009 Location: Kansas City Status: Offline Points: 1268	Post Options Post Reply Quote Greyhounds_AMX Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 11:52am
	Interestingly, the Mustang II front suspension uses strut rods as well, and they go to the rear like on our cars. The MII suspension is used on tons of street rods and Cobra replicas, so I'd expect if we dig deep enough we could find a number of different ways that the strut rod has been modified over the years. One that seems interesting is to convert the strut rod into a simple suspension bushing like used on the control arm. Then I suppose the impact loads delivered from the front of the tire are taken by the two bushings, one in compression and one in tension. That's pretty standard for modern control arms today. On ground up street rods they integrate it into a new replacement lower control arm: Or they use a custom strut rod with a bushing at the rear mounting point, and weld a bracket to the frame for the mounting point. As long as the lateral distance is equal from the ball joint to each bushing, there will be no binding. Here's a version of that setup: And a kit version: This really might be worth trying on our cars. I think the frame mounting area is at about the correct distance, so we'd have to do a bit of fab work to make a new rod and new mounting. But it would eliminate any binding and still have good isolation so the ride quality wouldn't suffer at all. Penny for your thoughts, guys...
	1968 AMX 390 w/T5

Greyhounds_AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Nov/14/2009 Location: Kansas City Status: Offline Points: 1268	Post Options Post Reply Quote Greyhounds_AMX Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 12:41pm
	For most average AMC cars I'd expect the desire would be to keep as much of the stock stuff as possible, to make it simple, strong, reliable, and pretty much stock appearing. For that situation we'd have to keep the strut rod as it is, but address the mounting point configuration. What 304-dude was doing with the ball design is dead-on the right approach, in that it needs to be a ball joint configuration. I think the trick will be finding something that gives the rotational freedom we want but also keeps the NVH to a minimum. I found two aftermarket versions of the ball type joint for the rear mount, designed for Mustang of course. The first is from Maier Racing, and uses a Delrin (hard plastic) ball that is split down the middle and used to sandwich the frame mount. Then Aluminum radius cups contain the ball halves. It's cool, but $500 for a pair and I expect would be rather harsh, as it's more of a race item. Here it is: A similar but cheaper version is available from Opentracker Racing, for $100 a set. Again, they use a Delrin ball but with steel containment, so NVH would be the same as the Maier. Here it is: I'm considering trying the Opentracker setup, but casting replacement ball segments from some relatively high hardness polyurethane in order to soften the ride. I'd think that would get us everything we'd want in a street car application.
	1968 AMX 390 w/T5

304-dude Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9082	Post Options Post Reply Quote 304-dude Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 1:11pm
	Greyhound, that is some great finds... A note about ball joint and harness. My design uses the factory mounting bracket's hole to center the ball. The space between the ball and bracket's round opening is taken up by the remaining Poly bushing's built in locating ring. By sheer coincidence, the 35mm ball cutter shaves just enough material to make the .5 mm lip as a cushion between ball and steel. It gets compressed to snuggly fit the ball in location. Another odd thing overlooked until you see the full function of how the curved washers are to slide over the poly bushing once the flats are domed. To assist with lube free frictionless pivot, the Teflon washer will allow the stock curved washer to function better, as it has a flat bottom. The ball itself is used to locate, and barely takes a load for any given time. So think of the poly bushings as stationary blocks and the curved washers press the blocks to sandwich the ball, so that the rod will pivot and all loads are pressed against the bushing. You may get away with Virginia nylon balls, as long as there is poly material between the bracket hole and ball. I agree Opentracker is the best setup period, though I never heard or seen such of a product until now. The only thing I recommend that is not expressed or shown, is using an old sleeve cut to fit the proper measurement for caster and welded or press fitted with the inner large nut, to strengthen the bind at the open threads. That part I have yet to do, as my custom suspension has not been shifted yet.
	71 Javelin SST body 390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker

Mopar_guy Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4823	Post Options Post Reply Quote Mopar_guy Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 6:42pm
	I like that Opentracker setup as well. The issue with the street rod type bracket is clearly showing in the picture you posted - the tire can hit it with a hard turn especially if you have wide wheels. I've seen that on street rods before.
	"Hemilina" My 1973, 5.7 Hemi swapped Javelin

tomj Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7544	Post Options Post Reply Quote tomj Report Post Thanks(0) Quote Reply Posted: Oct/29/2017 at 9:40pm
	i approve of this thread... even though i'm unlikely to have a strut suspension. ever, i hope. lol. but the strut does work, in my experience the quality of parts was the issue, not design, so much. for non-racing stock apps, at least.] funny, i stumbled upon the pics of the system i had in my '70 hornet. i had all sort of horrors in that car; washers that pushed through crap rubber, etc. then found some set that had a cap and cup, very michj like the delrin/alum setup greyhound posted. if the lower arm isn't damaged, and you have good bushings, and you have good strut bushings, it does work and does stay in alignnment. sadly thats a lot of ifs (that would have been no-brainers 15 years ago).
	1960 Rambler Super two-door wagon, OHV auto 1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19676	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Oct/30/2017 at 7:31am
	The only problem with these delrin/metal combos is the shock transmitted into the car. Put a 1" thick flat rubber donut on the front between the shoulder or adjusting nut and the front metal cup and you should have something that works better and absorbs about as much shock as the stock setup. The metal/delrin setups work fine for track and some would find them okay for street, but the Mustang II rubber bushings work well (they fit Mustang II and AMC) for most. It's fine to look for a better way, but the "better ways" are usually use specific. I've re-engineered a lot on my car, so you guys continue to go for it! I'm not trying to rain in the parade...
	Frank Swygert

Greyhounds_AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Nov/14/2009 Location: Kansas City Status: Offline Points: 1268	Post Options Post Reply Quote Greyhounds_AMX Report Post Thanks(0) Quote Reply Posted: Oct/30/2017 at 7:41am
	I was planning to make a mold of the delrin ball segmants and cast replacements in polyurethane. I suppose it'd have to be relatively high Shore hardness though to give good wear life.
	1968 AMX 390 w/T5