QA1 Six-Link Rear Suspension Conversion Installed

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I know he is. And I also know he's asked for my input a few times too.

I only asked for input when I first got the A- Body car I am working on in March of this year. I've always stayed away from them. You really didn't have anything ground breaking you have done. I was planning on just low buck upgrades for a car to beat around in on the street. But with over 700hp on tap I really can't see just going with 295 tires out back with an offset shackle kit and Hamburg swaybars. I did that in high school. And no it doesn't have leafs anymore. They won't work for what I am doing.

So, I scrapped most of it, and went in a direction of going overboard and not building the cheap route. If I am going to be in there cutting and welding, I might as well do it for the two purposes I see the car being used. So it's a compromise all around. I 've built several Mopar's and have owned a '70 Barracuda for 32 years now. (And that's an all aluminum Hemi)... So, no I don't agree that Chrysler had all of these cars designed perfectly. I know they didn't. I had too many of them.

My point is this. If all of you sit around and whine about every new product that comes out from a company that takes interest in our old Mopars, they won't spend the time to bother with us. Detroit Speed took up an interest in our old cars 5 years ago. And they abandoned it because the feed back was "Mopar guys like the originality of their cars more than performance". This from a company that designs top notch suspension systems for Chevy's and Ford's but not a Mopar (Which has suspension that has common cross platforms). And yes their Quadralink system is what most of the guys are running that want a car to handle. So, I'm left with mini-tubbing and narrowing having custom swaybars bent. While you guys screw around telling everyone about your bolt on mods, I've actually spent time fabbing my own parts and it gets costly and above all time consuming. It would be great if I could just go to someone like Detroit Speed & Engineering and buy a system that works and has success on the track too.

And that's where none of you are doing anything ground breaking other than typing "I can make my own 4-link rear suspension". Sure you can, in your dirt driveway, sitting on jack stands made from cinderblocks and used tires! And you guys amaze me with your skill at narrowing rear housings with no narrowing jig! Wow, you guys are so amazing!

The only thing I can see QA1 did wrong was caving in to purist who won't cut up a Mopar and actually having a completed car done for comparisons. But still I'm interested in what they accomplished.

And talk about a hypocrite 72BluNBlu, didn't you screw up installing your Hotchkis UCA's? And that's why you constantly write about how Heim joints are junk. That's funny I use them on suspension test fixtures everywhere for 20 years now and they last up to 4 million cycles. Funny yours puked out at 7,000 miles.
 
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Unfortunately there is not something that does it all....even with cutting.....but that is what most expect.

IMO ....to maximize performance in one catagory, you loose in another. A throw down drag race set up is very different than a autocross package....and it is hard to beat leaf springs for cheap but effective street suspension. I have tried all the different bushings with my 4-bar, ran in parallel and ladder bar configurations and for a nice street ride.....stick with rubber bushed leaf springs .

BTW....I have a concrete driveway and HD jackstands.
 
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I only asked for input when I first got the A- Body car I am working on in March of this year. I've always stayed away from them. You really didn't have anything ground breaking you have done. I was planning on just low buck upgrades for a car to beat around in on the street. But with over 700hp on tap I really can't see just going with 295 tires out back with an offset shackle kit and Hamburg swaybars. I did that in high school. And no it doesn't have leafs anymore. They won't work for what I am doing.

So, I scrapped most of it, and went in a direction of going overboard and not building the cheap route. If I am going to be in there cutting and welding, I might as well do it for the two purposes I see the car being used. So it's a compromise all around. I 've built several Mopar's and have owned a '70 Barracuda for 32 years now. (And that's an all aluminum Hemi)... So, no I don't agree that Chrysler had all of these cars designed perfectly. I know they didn't. I had too many of them.

My point is this. If all of you sit around and whine about every new product that comes out from a company that takes interest in our old Mopars, they won't spend the time to bother with us. Detroit Speed took up an interest in our old cars 5 years ago. And they abandoned it because the feed back was "Mopar guys like the originality of their cars more than performance". This from a company that designs top notch suspension systems for Chevy's and Ford's but not a Mopar (Which has suspension that has common cross platforms). And yes their Quadralink system is what most of the guys are running that want a car to handle. So, I'm left with mini-tubbing and narrowing having custom swaybars bent. While you guys screw around telling everyone about your bolt on mods, I've actually spent time fabbing my own parts and it gets costly and above all time consuming. It would be great if I could just go to someone like Detroit Speed & Engineering and buy a system that works and has success on the track too.

And that's where none of you are doing anything ground breaking other than typing "I can make my own 4-link rear suspension". Sure you can, in your dirt driveway, sitting on jack stands made from cinderblocks and used tires! And you guys amaze me with your skill at narrowing rear housings with no narrowing jig! Wow, you guys are so amazing!

The only thing I can see QA1 did wrong was caving in to purist who won't cut up a Mopar and actually having a completed car done for comparisons. But still I'm interested in what they accomplished.

And talk about a hypocrite 72BluNBlu, didn't you screw up installing your Hotchkis UCA's? And that's why you constantly write about how Heim joints are junk. That's funny I use them on suspension test fixtures everywhere for 20 years now and they last up to 4 million cycles. Funny yours puked out at 7,000 miles.

Again with the "whining" comments. It's not whining. It's constructive criticism of the pros and cons of a certain suspension system. They all have them. Any company that builds suspension should know this, and will understand their product won't be for everyone. Most of the criticism of the QA1 system comes straight from their own installation instructions- can't use tailpipes, must use all the stock locations for suspension mounting (limiting tire width), etc. They're already aware this product won't be for everyone, they designed it that way.

I've never shortened a rear axle housing without a jig, and I actually have a jig for doing just that. I don't have a dirt driveway. And honestly, if you know how to use a level and a plumb bob, having a dirt driveway is in fact irrelevant. If I did my own four link, I would design it on my computer with a CAD system, because yeah, I was an engineer. And I'd run it through suspension software. And again, if you can use a ruler, you don't need a CAD system either. Just a piece of paper and a good straight edge. Not that many folks out there do hand drafting anymore, but there's nothing wrong with it. My calculator has more computing power than the computers used for the Apollo program, you don't need fancy crap to do big things if you know what you're doing.

As for my Hotchkis UCA's- I purchased the original UCA's right after they came out, when they did not come with boots to keep dirt out of the heims. They lasted 7k miles of street driving before they wore out. When that happened, I posted about it on another forum. Hotchkis' representative on that site contacted me, and I shared detailed pictures of my installation, alignment settings, frame rails and suspension mounts, etc. Hotchkis sent me replacement heims because they could find nothing wrong with anything I did. They even included the boots that now come with their UCA's, because they realized that it was an issue to run without boots on the street. Even with the boots, that set of heims is starting to show signs of wear after another 7k miles. They're not worn out, but I doubt they'll see 10k. There was and is nothing wrong with my install, and Hotchkis confirmed that themselves.

If you know so much about engineering, you'll understand that what works on a test jig isn't real life. It's not an accurate representation of what happens in the real world. Which is why, despite having test rigs that can approximate millions of cycles in all weather conditions, all of the major auto-manufacturers still do extensive real world testing before they release a product. Because what happens on a test fixture isn't what happens in the real world. Heims don't like dirt. The don't like all weather conditions. Which is why I would never recommend them for use on the street. That is not just my opinion either. If you frequent any other boards that are racing specific, you will find plenty of recommendations that say that heims are for race cars, not street cars, and not even cars that spend most of their time on the track but still see the street.

And, I AM interested in seeing what the QA1 system is capable of. Which is why I keep saying that. But given the disaster of a thread this has turned into, if I were the OP I'd never post here again.

Unfortunately there is not something that does it all....even with cutting.....but that is what most expect.

IMO ....to maximize performance in one catagory, you loose in another. A throw down drag race set up is very different than a autocross package....and it is hard to beat leaf springs for cheap but effective street suspension. I have tried all the different bushings with my 4-bar, both ran in parallel and ladder bar configurations and for a nice street ride.....stick with rubber bushed leaf springs .

BTW....I have a concrete driveway and HD jackstands.

Exactly so Denny. All suspension is about compromise. Which is why your suspension is so great, because you truly understand that.
 
Thanks.

I do applaud Qa1's effort, but my gut reaction when I first saw it was this was engineered by someone that has never hot rodded a Mopar ....looks pretty, but (IMO) pretty without function is only good for the brand Xers, not for most Mopar fanatics. Maybe time will prove me wrong....happens a lot!!! (once again, just ask my wife)

I do use a lot of Qa1 shocks and other Qa1 products. I deal with Marshall Felgar (Qa1) and his support for the products is fantastic.
 
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Actually I am a Mechaical Engineer in automotive. And car suspension is tested on jigs on a test stand that replicates the vectors of motion that particular car suspension goes through. We change the loads applied and angles the force is applied. We also test each part over and over individually to break them. And they are tested in rooms that replicate temperature and conditions (salt spray). I know, I've been designing the test equipment for years. But our Heim joints (albeit way bigger) are larger for increased loading. (We actually can see 1/4" up/down or side to side movement in the upper ball joint location on cast iron steering knuckles during testing).

I can tell you that a Hiem joint will always have a premature life if it's "swivel" is out more than 5 degrees total. Best not to have them swivel at all on the ball, We blow through them if there is a problem with a fixture design and the load we apply changes the vector more than that. When we correct the fixture design misalignment, the Hiem's durability drastically goes up. And with parts changing all the time from R&D changes to increase strength and the constant drive to use the least amount of material to make a part, loads are going everywhere. A part aligned on one fixture, becomes misaligned when it is revised with changes.

No, I wouldn't want Heim joints everywhere because of the harshness (they aren't an insulator) and the damage they can cause where they mount is the biggest negative. And you can't really run a Heim joint if it is swiveling more than 2.5 degrees off the shaft its mounted to when you apply heavy loads. No, it's not 11 degrees or what ever the manufacturer says it can swivel. Machine/fixture designers know this. Actually poly/rubber bushings and adjustable links seems to be the best for cars driven on the street.

With that said, look at how BMW eliminated A-arms in the front of some of their cars. Everyone said that was junk, over engineered, all those links will bind at GM. Then a year later GM was copying it in their G8 prototypes. It proved better for handling.

All of that doesn't mean we shouldn't look at the investment QA1 made in this system and see how it actually performs with an eye to being positive. There are draw backs to all suspension. Torque arms can have squat and brake hop problems, 4- link's can bind with lateral loads, 3-link can eat up space where the 3rd link to properly adjust pinion angles, leaf springs can twist in weird shapes and change pinion angles and can bind. It's all blah blah blah... Because someone might just find a way to make something work in any of them.

Where's the guy that said at SEMA this out performed a new Challenger/Charger?
 
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This is nothin'.....just a little bench talk, wait till someone goes in the can and a bottle rocket gets slipped under the door. Heck, we used to get hotter than this talking about each others girlfriends.

Remember the good ol' days sitting around the local gas station uptown BSing .....this is just the internet version..
 
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This is the difference between when a Aerospace Engineer tells you there is no room on a Heim joint to fit grease zerk 100's of time on social media, and a Mechanical Engineer who actually works with this stuff. The oil impregnated bronze liners would blow their mind.
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Who sells those?

Just about everyone. Google them. They've been used in industrial machinery applications since I've been in engineering the past 30 years. I even see them at farm implement dealers like John Deere, International, White...
 
Just about everyone. Google them. They've been used in industrial machinery applications since I've been in engineering the past 30 years. I even see them at farm implement dealers like John Deere, International, White...
gotcha. those are usually pretty heavy, so it's a trade off im assuming?
 
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No, they make greasable ones in all sizes. And a lot of parts and boots no body knows exist.
 
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And if you severely swivel a Heim to one side, you run the risk of it being free on one side, and binding on the other. It will dig a groove in the ball usually on one edge and the edge on the other opposite side when the force vector tries to force the ball on a outside corner.
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Well since this thread is already hijacked I guess I'll ask here, what's the difference between a heim joint and a uniball? Or is there none?
 
Let me try....

A uniball is like a heim without a shank, it fits into a unthreaded socket, normally held in place with a C clip.

The heim is normally held by either male or female threads on a shank

I used them in the early stages of development in place of a upper ball joint to raise the upper control arm pivot

Like a heim, they have limited movement that limited suspension travel. Dirt track guys use them, that is were I came across them.
 
I am in the process of getting my dart in to this century. I looked at the QA1 front suspension and was quite surprised when they said their system don't use the rack n pinion steering, just the old steering box, center link, etc, etc. I believe QA1 is in fact a respectable name brand in suspension, but why would they try to talk me into keeping the outdated steering components. Is there a problem with putting a rack in? Some incite on this matter?
 
I am in the process of getting my dart in to this century. I looked at the QA1 front suspension and was quite surprised when they said their system don't use the rack n pinion steering, just the old steering box, center link, etc, etc. I believe QA1 is in fact a respectable name brand in suspension, but why would they try to talk me into keeping the outdated steering components. Is there a problem with putting a rack in? Some incite on this matter?
theres a lot of people in the mopar hobby that dont like the idea of using Mustang II style spindles, which most other coil over kits use, HDK,GTS,RMS etc. Because of the angles and how the mopar spindles are, it's extremely difficult to get the correct geometry to go rack and pinion and use the rear steer mopar spindles. I'm sure Denny or Carl will chime in as to that as well. and if I recall right, the QA1 kit retains the factory Torsion bars which a lot of people like that as well.
 
theres a lot of people in the mopar hobby that dont like the idea of using Mustang II style spindles, which most other coil over kits use, HDK,GTS,RMS etc. Because of the angles and how the mopar spindles are, it's extremely difficult to get the correct geometry to go rack and pinion and use the rear steer mopar spindles. I'm sure Denny or Carl will chime in as to that as well. and if I recall right, the QA1 kit retains the factory Torsion bars which a lot of people like that as well.
No they did utilize their coil overs but for the steering the old style hardware had to be used.
 
No they did utilize their coil overs but for the steering the old style hardware had to be used.
Um.....no. they use Torsion bars.

Handling Suspension Kits for 1967-1972 Mopar A-Body | Dart, Demon, Duster, Valiant & Scamp Full-Vehicle Suspension Upgrade | QA1


http://www.qa1.net/tech/documents/52313, 52314_REV_8-16-2013 Mopar K-frame.pdf

from their own instructions:

"3. Count the number of revolutions it takes to remove the tension from the torsion bar adjusters in the lower control arms. Take note of this and use it during the assembly process to duplicate the ride height."

"Clock the torsion bar keys and re-install the torsion bars and snap rings. The K-member may need to be adjusted in the car to get the snap rings in and fully seated in the grove and for proper engine placement. 6. With the torsion bars in place, the lower control arms can be reattached to the ball joints. Tighten the ball joint nuts to factory specifications and install new cotter pins in ball joints. 7. Tighten the torsion bar adjusters the same number of turns required to remove"
 
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