Need new suspension

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Idaho said:
I don't doubt your experience. I guess it means the parts were built strong enough to function in a position that would normally be the result of upward deflection. Are your control arms about level after lowering?
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Keep in mind that the suspension isn't ever static. Yes, with the car lowered the ball joints will spend more time in a position that was more toward the "edge" of their operational window, but its not like the ball joints were never in that position on a stock car. With the stock marshmallow soft torsion bars the ball joints probably spend more time in that position than you might think. How many people complain about their cars always hitting the bump stops with the stock torsion bars? Lots. Constantly bashing the suspension parts into the bump stops is harder on them than anything else, and the factory parts did that for 10's of thousands of miles on 10's of thousands of cars.

And yes, the UCA's on my car are pretty close to parallel with the ground on my Challenger and my Duster. Neither car has more than an 1" of travel between the frame and the LCA bumpstop, and both have shorter, poly bumpstops on the LCA's. Full disclosure though, neither have stock UCA's. I have Hotchkis UCA's on my Challenger and Magnumforce UCA's on my Duster. The Duster will have double adjustable SPC UCA's on it here pretty soon.
 
The first pic shows the ball joint at an angle where its about to impinge on itself. The 2x2 is there showing about 1.5" from tire to upper inner fender. This may be somewhat above the ride height I was going for with just a little of the tire covered by the fender. If I recall it was just touching the upper bump stop. Sorry my memory is not the greatest.

The second pic is with the UCA touching the bump stop. This is an 18" wheel. I think it was a 245/45/18. A lot taller than factory. Anything taller would rub on the front of the fender. Raising the suspension much from there would expose the top of the tire. Not the look I want.

The third pic shows a test using clay showing that a 2" drop spindle would result in contact with the upper control arm with this particular wheel.

I decided the HDK was a good solution. My project is on hold so its waiting to be installed. To be clear, I am not an expert by any stretch, just sharing my limited experience.
 

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In the first picture your LCA pretty much has to be on the frame. It's hard to tell because of the angle of the picture, but the angle on the UCA is pretty much the absolute max it's capable of. That is not a realistic ride height by any stretch of the imagination. You would have pretty much zero suspension travel. None. Do you even have the camber bolts installed in that picture? I can see almost the entire adjustment slot on the UCA mount.

How tall are those tires? Even with the HDK, you'd need air ride to pull off what you're trying to do with the ride height.
 
245/45/18 is just under 27". Yes the camber bolts are in. I hear of others removing or shortening their bump stops and I see ride height with fenders covering tires (sublime69's is an example), so it seems like they are in this range. Were you able to get a ride height with the fender covering part of the tire?

What wheel/tire combo are you running sublime69?
 
Idaho said:
245/45/18 is just under 27". Yes the camber bolts are in. I hear of others removing or shortening their bump stops and I see ride height with fenders covering tires (sublime69's is an example), so it seems like they are in this range. Were you able to get a ride height with the fender covering part of the tire?

What wheel/tire combo are you running sublime69?
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Sorry, but there's no way you'd be able to drive a car on the street with the suspension set as you have it in that picture. I know you're going HDK, but on a stock set up that you'd never pull off that kind of angle on the UCA. Even with the HDK you'd need drop spindles to get that low, and I'm still not sure you'd get as low as your car is there without air ride. My fenders just barely cover the tops of my tires, maybe by a 1/4". It's enough that at full lock my tires barely clear the fender, and that's with a 25.6" tall tire up front (275/35/18 ). The top of the fender opening sits at 25" from the ground in the front. So, with a 27" tall tire you would have a significant amount of tire tucked in even at the height my car sits, although your fender opening would be higher off the ground because of the taller tires. You can see in this first picture that my LCA's are still slightly lower than parallel with the ground at their "flat" section. In this picture you can see that there's a little less than 1.5" from the frame to the LCA, and less than 1" from the frame to the bumpstop. I have since gone to even shorter bumpstops and lowered the car slightly, probably only a 1/4", so that the flat section of the LCA, and the UCA, are parallel with the ground at ride height and I have about 1" of travel at the LCA.

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Keep in mind that with your tires tucked like that you will be significantly limited in tire width and will have to run a ton of backspace if you actually intend to turn without the wheels hitting the fenders. Doesn't look like your wheels are at full lock in the pictures.
 
My car sits at just about 24" from the ground to the fender. 225 45 18"s. I had 245 X 40 18's before but they wore out and I got these used. No rubbing now either. My car has no bump stops left from driving it this low for that last 8 years. Everything is stock and original as well. Including the 6 cylinder bars. It surprisingly drives pretty nicely. I drive it everywhere too.
 
Sublime69 said:
My car sits at just about 24" from the ground to the fender. 225 45 18"s. I had 245 X 40 18's before but they wore out and I got these used. No rubbing now either. My car has no bump stops left from driving it this low for that last 8 years. It surprisingly drives pretty nicely. I drive it everywhere too.
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No bump stops left from driving = drives pretty nicely?

I don't even know what to say about that. You and I must have very different ideas about what it means to "drive pretty nicely".
 
By drives nicely I mean that it goes down the road straight. Takes bumps fine and corners ok. I can turn the wheel fully locked and go up curb with no rubbing. Again, why I started this thread was because I need to upgrade the suspension. I want it to actually handle and corner good. Not just "ok" for what it is.
 
I would go with PST 1.03" bars and Viking front shocks that I would custom order a bit shorter than factory. If the bar does not have enough spring rate to stop it from bottoming just add a few clicks of compression damping and stiffen it up.
The Viking shocks have a large range of damping, at the softest setting the front will bounce like it has no shocks and 10 to 12 clicks in it is stiff like a 1 ton truck. I will never put anything but double adjustable shocks on any of my cars again.
 
I'm gonna back up 'ol blu on this. Even with my limited knowledge and tinkering with KYB's and 1" bars, from where he has the tape, 1.5" will hit easily verified. 2" if your not careful. Less than that expect to be on the bump stops pretty much every time you leave the driveway. Maybe with stiff bars you can do 1.5 like he does. Obviously blunblu has put a bunch of R&D into getting the best out of his suspension. He seems fond of the topic. So I would use what he says as a solid baseline.

Also, it seems ride height and spring rates go hand in hand, I had mine set low and the damn front end was flipping around clattering like a fish, added another 1" to it. Way more firm and less wallow. Do what you want, but the lowest common denominator will determine ride height; fender clearance at full lock going up a curb, bump-stops and headers.
 
I am going to do new torsion bars, shocks and sway bars. So would I need to use drop spindles in order to maintain the same ride height?
 
Sublime69 said:
I am going to do new torsion bars, shocks and sway bars. So would I need to use drop spindles in order to maintain the same ride height?
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No, just less torsion bar preload. My car is about 1/2" higher than 72blunblu's and I still have the ability to go down with less preload without even trying.
 
goldduster318 said:
No, just less torsion bar preload. My car is about 1/2" higher than 72blunblu's and I still have the ability to go down with less preload without even trying.
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The problem isn't the torsion bar adjusters, it's that you run out of suspension travel. Even where my car sits I only have about 1" of suspension travel from the bumpstop on the LCA to the frame.

Sublime69 said:
I am going to do new torsion bars, shocks and sway bars. So would I need to use drop spindles in order to maintain the same ride height?
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As much as I dislike them, I would say yes, you'll probably need drop spindles to stay that low.

My car sits at 24 7/8" at the wheel opening now, and that's with a 25.6" tall front tire. With my bumpstops changed out to 3/8" tall poly buttons, I have 1" of clearance from the top of the bumpstop to the frame. Even with 1.12" torsion bars (300 lb/in wheel rate) I occasionally bottom the suspension out on big potholes, etc. I don't need to raise the car any, but I'm pretty close to as low as I can go with the torsion bars that I have.

Now, a small change in distance at the LCA is much bigger change in distance at the wheel opening. But considering you have 26" tall front tires and want to run smaller torsion bars, I'd say you'd need more clearance than I have, not less. I've never bothered to check the exact relationship between the change in ride height compared to the change in clearance at the LCA. With the difference in tire heights I'd have to drop my car a full inch to be where you're at, and I don't think I could pull that off without being on the bumpstops frequently under normal driving conditions.

The only other thing you could consider doing would be changing over to the QA1 tubular LCA's. Because of their tubular construction their height profile is shorter, which basically means you get more suspension travel before they bottom out when compared to the stock LCA's. That would still leave you with a more severe angle on the UCA's though. And the additional travel might actually lead to interference between the top of the tire and the inner fender at full compression. Which is definitely an issue you can run into with the drop spindles too, by the way.

I have a set of the QA1 tubular LCA's to put on my car, haven't gotten around to doing it yet. They're going to go on at the same time as my new SPC adjustable UCA's so I only have to set the alignment once.
 
Ok thanks for all the info! I definitely have some research to do I guess. Just curious, how come you dislike drop spindles so much? Is there a common brand everyone uses here? Also, do you think I should go with the bigger torsion bars? I have a 6 cylinder k member too. If that matteres.
 
The best suspension geometry- roll center, camber curve, bump steer etc occur when the control arms are roughly parallel with the ground. That phenomenon happens when A-body's are lowered pretty significantly, basically where my car sits right now. But it's not quite a full 2" drop.

A 2" drop spindle lowers the car 2" while maintaining the stock control arm angles. That means that the camber curves stay about the same as the stock geometry. The roll center changes because the car itself is lowered, but it still isn't as good as what you get from lowering the car with the torsion bar adjusters. It stays the same relative to the car, and is lowered only because the car is. But most of that stuff is pretty minor. You basically keep the stock suspension geometry, but lower the car 2". The nice part is that you keep the same amount of suspension travel, so, you don't have to change the torsion bars. It basically lets you run any torsion bar you want and still drop the car 2" without worry about bottoming the suspension all the time, instead of having to go with some really big torsion bars like I've got to get that much drop.

The "problem" is that most folks don't drop their car a full 2". For example, you install 2" drop spindles, and then set the car up with a 1.5" drop compared to stock. Still a pretty significant drop compared to stock. But as far as your suspension geometry is concerned, you've actually raised your car a 1/2". Which will have actually made your suspension geometry even worse than stock. You had to compensate for the 2" spindle drop by using the adjusters to raise the car above where the stock ride height would have been.

So, that's my beef with drop spindles. The stock suspension will allow for more drop than most people usually want. If you match your drop in ride height with the appropriate sized torsion bar, you end up with better suspension geometry and better handling all the way around, and you don't have to drop $500 on spindles. Most folks that want to lower their cars also want them to handle better, so buying new torsion bars is something they would do regardless. Which means you have $500 you didn't spend on drop spindles to spend on something else.

The drop on your car though is at least 2" from stock. Which means as long as you keep your current ride height, you won't have the issues that come from running 2" drop spindles with a less than 2" drop in ride height. My only concern is that other issues come up, like the tires bottoming out on the inner fenders because the car is 2" lower but the available suspension travel is the same as a stock car.

As far as the drop spindles go, I would use PST or Magnumforce. I ran the Magnumforce drop spindles on my Challenger before I improved my knowledge of torsion bar suspensions. I probably put 30k miles on them without any issues. That was before PST sold them. Fatman also sells a set of drop spindles, but they're fabricated. I'm not a fan of welds in my spindles. I pulled the drop spindles on my Challenger when I redid some other suspension parts, and found I could lower the car to the ride height I wanted without them (and then some). So I pulled them and sold them. The Challenger handles better without them. Small caveat though, E-body's have a little more available suspension travel based on my experience with my Challenger compared to my Duster. The E-body's can be dropped with the stock suspension and larger bars until you can't even drive over speed bumps without leaving the exhaust behind. I've actually raised my Challenger up a bit from it's lowest, I got tired of dragging the headers everywhere I went. And those are above the steering link headers.

And of course I would go with the larger torsion bars regardless. The K frame doesn't matter, I assume you're using conversion mounts then?
 
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