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Discussion Starter #1
Well, I replaced every single point of rubber in my front suspension, new ball joints, new bushings everywhere, tie rods, etc, and my front end still sounds like people dropping ball bearings onto the ground from a ladder whenever I drive my pile of crap about to be scrapped mark viii i used to love.

I am about at my wits end with this car, and it was very nearly cut up to be a donor car for an FFR, and every so often I get pissed off at it, and remove just a little bit more of my interior.

I havent driven it in almost a year because the transmission took a crap after my last track outing, and I was busy with school, but now that im a working man, and I have a little money coming in, I have been reconsidering scrapping/cutting her up, and continuing my resto modding.

Now that my rant is over, I have been looking around on vintage mustang websites and have found that they have issues with their strut rods also, and that alot of people have either made or purchased solidly mounted adjustable strut rods.

I am using the instructions I found on this website

http://dazed.home.bresnan.net/adjustable

I was looking at it, and the design could be adapted to our cars. I am simply going to run one of those clevises at both ends obviously instead of the bolt on arm at the spindle.

I am looking around for a machine shop or a metal fabrication shop, because our cars have the bend in the strut rods, and I will need to have some tubing bent properly as well as threaded for the clevises.


Hopefully when all is said and done, this will finally eliminate my clunking, more solidly locate the spindle during hard cornering, and since I am going to be using aluminum bushings that are fitted, and bolts, it should eliminate the need to replace strut rod bushings every 70k miles.

I will keep you guys updated on my progress.

Also, any thoughts, ideas or opinions, even negative ones would be appreciated.

The car: 1995 Lincoln Mark VIII - coil conversion, new front control arms upper and lower, new strut rod bushings, new tie rods inner and outter, rear 5 on 4.5 lug conversion.
 

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I am simply going to run one of those clevises at both ends obviously instead of the bolt on arm at the spindle.
Two new pivots points is a HUGE mistake, think about it some more.
 

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Discussion Starter #4 (Edited)
fair enough, so I have.

But, right now, the stock strutrod setup has two pivot points, and they allow for motion in all directions including forward and backward which affects the suspension geometry during cornering, and is also what creates the "wallowing effect" that eats the bushings up.

True with my setup, I have 2 pivot points, but the motion is limited to only an up and down motion, which would limit the ability of the spindle to walk forwards and backwards (as it imperceptibly does), and additionally, the up and down travel of the control arm will be limited both by the spring/shock travel length, and the fixed overall length of the strutrod that wont change.

Also the second pivot point would do more to keep the front suspension travel true to its original design because even though there are two pivot points, the attatchment points must remain parallel to eachother. As the spring and shock would compress under a hard corner, the fixed length of the strut rod would essentially draw the spindle towards it. I should point out that I have almost the entire catalouge of supercoupe performance suspension stuff stuff from bill, and I am getting ready to go to a pretty stiff spring/shock setup, there isnt going to be as much suspension travel as stock anyway.

Think about a fresh pencil flat on both ends. stick it in the middle of both of your palms while they are flat facing eachother, then while opposite pressure keeping the pencil within the grip of your palms, keep your palms parralell to eachother and move them up and down in opposite directions while maintaining the grip.
 

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Discussion Starter #5
I was under the impression the strut rod's only job in this style of suspension setup was to prevent lower front to back movement of the lower control arm. If you guys think I am off base, or that that second pivot point could create a dangerous suspension issue, I can easily see how to make one that has the clevis frame side, and a fixed end on the other.
 

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I was under the impression the strut rod's only job in this style of suspension setup was to prevent lower front to back movement of the lower control arm. If you guys think I am off base, or that that second pivot point could create a dangerous suspension issue, I can easily see how to make one that has the clevis frame side, and a fixed end on the other.
I think that's a much better approach. Unless the pivot point at the LCA coincides exactly with the centerline of the LCA, you'll be changing the suspension geometry.

I think that using a heim joint in place of the forward bushing and retaining the stock bushings at the LCA would be the better solution.
 

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Now Im wondering if we could just find a company that makes Poly bushing for the strut rod alone at both ends instead of buying a whole kit for the car ?
 

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Discussion Starter #8
there are currently poly bushings available. they actually tear up faster than the rubber. because theres no give in the poly, the wallowing motion the strut rod makes just annhialates them. Also, I dont like the design of the bushing setup for the stock strut rod.
 

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Discussion Starter #9
DLF, I spent some time under the car today, and with an engineer friend of mine, and I noticed something.

The classic mustang strut rod is a different design than the lincoln setup. The outter end of the mustang strutrod is attatched to the spindle with thru-bolts mounted in a perpendicular north south orientation, whereas the outter end of the Lincoln strutrod simply penetrates through the lower control arm. The mustang can get away with a single pivot point at the frame, whereas this would have a different effect on the lincoln.

if I use the frame attatchment as my heim joint pivot point, a solid bushing like I wanted would create a binding issue at the other end with only 1 pivot point. If I use the stock rubber bushing at the control arm, it would be subject to the same deflection that shears and wallows the bushings in the first place.

the second pivot point maintains the correct geometry while eliminating binding, and eliminating the deflection.

I went back and re-read your original post, and I think that this double heim jointed setup is perfect.
 

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DLF, I spent some time under the car today, and with an engineer friend of mine, and I noticed something.

The classic mustang strut rod is a different design than the lincoln setup. The outter end of the mustang strutrod is attatched to the spindle with thru-bolts mounted in a perpendicular north south orientation, whereas the outter end of the Lincoln strutrod simply penetrates through the lower control arm. The mustang can get away with a single pivot point at the frame, whereas this would have a different effect on the lincoln.

if I use the frame attatchment as my heim joint pivot point, a solid bushing like I wanted would create a binding issue at the other end with only 1 pivot point. If I use the stock rubber bushing at the control arm, it would be subject to the same deflection that shears and wallows the bushings in the first place.

the second pivot point maintains the correct geometry while eliminating binding, and eliminating the deflection.

I went back and re-read your original post, and I think that this double heim jointed setup is perfect.
I certainly agree that the strut rod needs to pivot on both ends.

However, you'll need to ensure that the pivot point at the LCA is in the exact centerline of the current bushing mounting point on the LCA, or you will be changing the geometry. If the pivot point is closer to the front of the car then it is stock, the LCA will be pulled farther forward as it travels up and down. Ideally, IMHO, the pivot point at the LCA should be as far rearward as possible to minimize deflection.

I just can't envision how you are planning to use a heim joint in that position, unless you are planning to somehow embed a heim (or cross-axis) joint in the LCA.

I wish you luck with your project.

In fact, using cross-axis joints at both ends could possibly allow for the re-use of the stock strut rod, if you were to machine the LCA to accept one and make a mount for one at the forward K-Member mounting location.

However, I don't have enough knowledge regarding cross-axis joints to know if they would be able to handle the stresses.

Think about a fresh pencil flat on both ends. stick it in the middle of both of your palms while they are flat facing eachother, then while opposite pressure keeping the pencil within the grip of your palms, keep your palms parallel to eachother and move them up and down in opposite directions while maintaining the grip.
Using your analogy.....

Notice that the planes of your palms get closer together as you move your palms in opposite directions. And, if you shorten the pencil, then they get closer more quickly.
 

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Discussion Starter #11
awesome analogy, I understand what you are saying completely. I already discussed the possibility of the forward motion of the spindle with my friend, and in an all out track situation, he said it would be noticeable, although it would be predictable. For street applications, the tire of the sidewall would take up some of that motion, and additionally stiffer shocks and springs would lessen the overall travel, including the front to back drift. Again though, because this would result in front to rear travel of a set length, it would be a predictable handling characteristic. I may be able to tune it out with different alignment settings/strutrod lengths.

I will keep you posted, thank you for your continued feedback.
 
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