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Old 09-15-2020, 01:25 PM   #1
Low Elco
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A 2-link question-

So, I just bought a 78 SWB, and have done several 67-72's. It will receive a cammed/tuned 5.3/4l60. I like the trailing arm ride and traction/handling advantages. But, I'm cheap, not a lot of dough here, and all of the kits are $$$$.

That has lead me to thinking. I intend to put the gas tank in the rear, which means nice, smooth rails all the way up under the cab. What If I took stock 67-72 trailing arm geometry, took the stock 78 forward spring hangers and flipped them, used basically a flip kit to mount the arms underneath (or just flipped the saddle over, or made saddles 67-72 style, only straight) and then adjusted for pinion angle. Make a bracket for the spring and a crossmember to reinforce at that point. Long travel shocks and a long panhard out back of the rear, a'la the No Limit kit.
3rd Gen WS6 swaybar somewhere in the mix. Wha-la, basically the same thing as a 67-72 setup, only outboard. I've been a fabricator for a long time, making the parts isn't a problem.

Anybody see anything glaringly wrong with this?
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Old 09-16-2020, 10:07 AM   #2
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Re: A 2-link question-

Quote:
Originally Posted by Low Elco View Post
So, I just bought a 78 SWB, and have done several 67-72's. It will receive a cammed/tuned 5.3/4l60. I like the trailing arm ride and traction/handling advantages. But, I'm cheap, not a lot of dough here, and all of the kits are $$$$.

That has lead me to thinking. I intend to put the gas tank in the rear, which means nice, smooth rails all the way up under the cab. What If I took stock 67-72 trailing arm geometry, took the stock 78 forward spring hangers and flipped them, used basically a flip kit to mount the arms underneath (or just flipped the saddle over, or made saddles 67-72 style, only straight) and then adjusted for pinion angle. Make a bracket for the spring and a crossmember to reinforce at that point. Long travel shocks and a long panhard out back of the rear, a'la the No Limit kit.
3rd Gen WS6 swaybar somewhere in the mix. Wha-la, basically the same thing as a 67-72 setup, only outboard. I've been a fabricator for a long time, making the parts isn't a problem.

Anybody see anything glaringly wrong with this?
I'm trying to picture what you're describing... Which 'link' style is your intent (leaf-spring or the T/A)?

Are you suggesting relocating the front leaf hangers inboard of the rails, using 67-72 T/A's as the suspension links/arms, & making a spring x-member to locate the coils @ the upper position?
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

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Old 09-16-2020, 10:40 AM   #3
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Re: A 2-link question-

Yes, but T/A outboard of the rails.
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Old 09-16-2020, 10:47 AM   #4
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Re: A 2-link question-

I,ve seen ones like this but with air bags.Is that what your thinking ?
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Old 09-16-2020, 11:38 AM   #5
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Re: A 2-link question-

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Originally Posted by Low Elco View Post
Yes, but T/A outboard of the rails.
So T/A's instead of leaf springs in the leaf springs original mounting position?
The leaf springs over-all length is about the same as a T/A (leafs @ 52-56"; T/A @ ~51"). However, the leaf locates the rear housing mid-length of the spring pack where the T/A is much farther rear ward. This would require moving the hangers forward.

If this is what you meant, the difference is the original mounting position places the T/A's in a triangle configuration which allows for some articulation. Combing the triangulated front mounting w/the I-beams ability to slightly twist & return to form as well as rubber bushings @ the front mount allow the system to flex.

Mounting in an 'H' or 'U' pattern is going to significantly limit that small amount of flex.
It's also going to impact the pinion angle changes throughout suspension travel & would need to be kept in mind.

2-links can work w/some effort but there are better ways to get things done vs re-purposing OE T/A's.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-16-2020, 11:39 AM   #6
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Re: A 2-link question-

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Originally Posted by blazer2007 View Post
I,ve seen ones like this but with air bags.Is that what your thinking ?
That's 'bind city' right there....
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-16-2020, 11:43 AM   #7
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Re: A 2-link question-

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Originally Posted by Low Elco View Post
Yes, but T/A outboard of the rails.

TA's or trucks arms triangualte in the center crossmember, and work very well.

What you described is a parallel 2 link, and they work fine. If cruising or profiling is what your after. Due to the bars being parallel there is virtually no twist, and it makes the truck feel stiff if you take corners to fast. Along with a excessive amounts of understeer. Since the rear end will not allow the truck to rotate.

The TA gets away with this by large bushings, and the mythical connection point in front of the truck.

So if your goals are to cruise the truck, and haul trailers. The parallel 2 link will work fine. If you want to tear up some corners. I would save for a TA set up or swap one in if you can find the donor parts.

For the parallel 2 link the longer the bars are the better they comply. So if you can get 3 or 4 foot bars in the truck I would do it. Short one make for more extreme pinion angle changes. Also a fixed trans yoke with a slipper driveshaft supposedly helps out alot. Or I set the trans slip yoke dead center to help stop binding.
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Old 09-16-2020, 12:05 PM   #8
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Re: A 2-link question-

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Originally Posted by blazer2007 View Post
I,ve seen ones like this but with air bags.Is that what your thinking ?

Nominally this idea, but with stock 67-72 length T/A's. Is this yours and do you like it?
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Old 09-16-2020, 12:07 PM   #9
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Re: A 2-link question-

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Originally Posted by SCOTI View Post
So T/A's instead of leaf springs in the leaf springs original mounting position?
The leaf springs over-all length is about the same as a T/A (leafs @ 52-56"; T/A @ ~51"). However, the leaf locates the rear housing mid-length of the spring pack where the T/A is much farther rear ward. This would require moving the hangers forward.

If this is what you meant, the difference is the original mounting position places the T/A's in a triangle configuration which allows for some articulation. Combing the triangulated front mounting w/the I-beams ability to slightly twist & return to form as well as rubber bushings @ the front mount allow the system to flex.

Mounting in an 'H' or 'U' pattern is going to significantly limit that small amount of flex.
It's also going to impact the pinion angle changes throughout suspension travel & would need to be kept in mind.

2-links can work w/some effort but there are better ways to get things done vs re-purposing OE T/A's.

Intention is to move spring mounts forward, to mirror stock 67-67 lengths.
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Old 09-16-2020, 12:25 PM   #10
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Re: A 2-link question-

Quote:
Originally Posted by Ziegelsteinfaust View Post
TA's or trucks arms triangualte in the center crossmember, and work very well.

What you described is a parallel 2 link, and they work fine. If cruising or profiling is what your after. Due to the bars being parallel there is virtually no twist, and it makes the truck feel stiff if you take corners to fast. Along with a excessive amounts of understeer. Since the rear end will not allow the truck to rotate.

The TA gets away with this by large bushings, and the mythical connection point in front of the truck.

So if your goals are to cruise the truck, and haul trailers. The parallel 2 link will work fine. If you want to tear up some corners. I would save for a TA set up or swap one in if you can find the donor parts.

For the parallel 2 link the longer the bars are the better they comply. So if you can get 3 or 4 foot bars in the truck I would do it. Short one make for more extreme pinion angle changes. Also a fixed trans yoke with a slipper driveshaft supposedly helps out alot. Or I set the trans slip yoke dead center to help stop binding.
This truck won't be a road racer, but will have upgraded brakes (3/4 ton calipers and 2 1/2" drums) and big swaybars in urethane at each corner. Approximately 5/7 drop. I'm more of a Cannonball type of guy, but I do enjoy me some mountain/hilly roads.

Mainly looking for the better ride, ride height adjustability, and lack of axle wrap that T/A's provide.

Not arguing, just thinking through- Is not a leaf setup also a parallel 2-link by virtue of a more or less solid connection at the front hanger to the rear?

A lot of the big diesel guys use ladder bars to fight rotation in the leaves, which is nominally the same thing?

Also, this would also be panharded side/side.

Intention is to use the stock 67-72 T/A length, and move the front hangers forward, which would effectively lengthen the T/A's a tad by pulling them to perpendicular to the rearend, then mount the shocks off the end of the T/A's like the NO Limit kit, and notch the frame and do a long Panhard set level at ride height.

Then again, I might just get lazy and flip kit it and be done.

Thanks for the responses, just food for thought.
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Old 09-16-2020, 12:54 PM   #11
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Re: A 2-link question-

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Originally Posted by Low Elco View Post
This truck won't be a road racer, but will have upgraded brakes (3/4 ton calipers and 2 1/2" drums) and big swaybars in urethane at each corner. Approximately 5/7 drop. I'm more of a Cannonball type of guy, but I do enjoy me some mountain/hilly roads.

Mainly looking for the better ride, ride height adjustability, and lack of axle wrap that T/A's provide.

Not arguing, just thinking through- Is not a leaf setup also a parallel 2-link by virtue of a more or less solid connection at the front hanger to the rear?

A lot of the big diesel guys use ladder bars to fight rotation in the leaves, which is nominally the same thing?

Also, this would also be panharded side/side.

Intention is to use the stock 67-72 T/A length, and move the front hangers forward, which would effectively lengthen the T/A's a tad by pulling them to perpendicular to the rearend, then mount the shocks off the end of the T/A's like the NO Limit kit, and notch the frame and do a long Panhard set level at ride height.

Then again, I might just get lazy and flip kit it and be done.

Thanks for the responses, just food for thought.
You can make a suspension w/them as you described but it won't work (articulate) the way you desire 'as-is' for canyon/hilly drives. You could do a spherical bearing @ the front mounts for some ability to rotate.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-16-2020, 03:50 PM   #12
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Re: A 2-link question-

I was considering Johnny Joints/those new ART joints. Hmm. It'll be interesting, I just got this thing Saturday. I'm also looking at the interesting idea of a Camaro IRS. We'll just have to wait and see what happens after the rust repair.
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Old 09-18-2020, 09:12 AM   #13
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Re: A 2-link question-

Quote:
Originally Posted by Low Elco View Post
Nominally this idea, but with stock 67-72 length T/A's. Is this yours and do you like it?
No, is some pics I saved when I was looking for AOL air bags setups
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Old 09-19-2020, 12:30 AM   #14
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Re: A 2-link question-

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Originally Posted by SCOTI View Post
You can make a suspension w/them as you described but it won't work (articulate) the way you desire 'as-is' for canyon/hilly drives. You could do a spherical bearing @ the front mounts for some ability to rotate.
It still won't rotate unless they "come together" in front of the bumper. Just like factory TA's where they would mythically meet about a foot in front of the truck. By virtue of being parallel they will effectively lock the axle in postion.

Dangerous for driving. No, but when pushed the truck now feels slow to react.

I helped a kid build a 2 link to get it on the road quick, and cheap. While we were testing it I had it at 90mph cruising, and it felt fine. Where I lived we 1 twisty road a block away. 25-30 mph which was the speed limit no issue. Get her to 45mph , and it felt decidedly awkward. We eventually swapped to a Impala SS triangualted rear end. I am not sure why he wanted that, but it was on a magnitude of 1000% better for corners.

Would I do a 2 link. Probably not unless I had threaded bushings laying around for some reason, and only had 4. But I would not discount them for a guy who just wants to profile.

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Old 09-19-2020, 02:10 AM   #15
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Re: A 2-link question-

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Originally Posted by Ziegelsteinfaust View Post
It still won't rotate unless they "come together" in front of the bumper. Just like factory TA's where they would mythically meet about a foot in front of the truck. By virtue of being parallel they will effectively lock the axle in postion.

Dangerous for driving. No, but when pushed the truck now feels slow to react.

I helped a kid build a 2 link to get it on the road quick, and cheap. While we were testing it I had it at 90mph cruising, and it felt fine. Where I lived we 1 twisty road a block away. 25-30 mph which was the speed limit no issue. Get her to 45mph , and it felt decidedly awkward. We eventually swapped to a Impala SS triangualted rear end. I am not sure why he wanted that, but it was on a magnitude of 1000% better for corners.

Would I do a 2 link. Probably not unless I had threaded bushings laying around for some reason, and only had 4. But I would not discount them for a guy who just wants to profile.
Define "rotate"? I'm not talking about full articulation. I'm thinking more about eliminating immediate bind ( which as you alluded to can be very unpredictable).

With a spherical joint @ the front, the fixed rear end will get some ability to rotate w/o immediate bind. Any sort of fixed rubber poly bushing would be in immediate bind. I'm not saying I'd do a 2-link/Billy-Bar set-up but if I had to offer ideas to improve one, some ability to rotate would be my first suggestion.

I've ridden in more than one truck set up w/the solid 2-links. I was surprised the ride was decent but from my perspective any uneven surface seriously stressed mounts & hardware from the bind. One guy kept losing the shocks (they were mounted like the image above). I walked him through the motion of things when the suspension changes heights differently @ each side. He had the shock mounts re-clocked & that eliminated the issue. I guess that could be luck or could be from a deffective initial install, IDK.
I also recommended going to a 4-bar.....
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-19-2020, 04:15 PM   #16
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Re: A 2-link question-

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Define "rotate"? I'm not talking about full articulation. I'm thinking more about eliminating immediate bind ( which as you alluded to can be very unpredictable).

With a spherical joint @ the front, the fixed rear end will get some ability to rotate w/o immediate bind. Any sort of fixed rubber poly bushing would be in immediate bind. I'm not saying I'd do a 2-link/Billy-Bar set-up but if I had to offer ideas to improve one, some ability to rotate would be my first suggestion.

I've ridden in more than one truck set up w/the solid 2-links. I was surprised the ride was decent but from my perspective any uneven surface seriously stressed mounts & hardware from the bind. One guy kept losing the shocks (they were mounted like the image above). I walked him through the motion of things when the suspension changes heights differently @ each side. He had the shock mounts re-clocked & that eliminated the issue. I guess that could be luck or could be from a deffective initial install, IDK.
I also recommended going to a 4-bar.....
I am not the best at suspension mods as I have always followed preordained formulas, and I could feel what they were supposed to do.

In your last paragraph you pretty much say what is wrong with 2 links. They ride fine, haul weight fine, but the have effectively no side to side articulation. Since the whole rear axle assembly now is effectively like a large sway bar. I described the issue when I pushed the truck quicker down a small twisty road. As i don't remember it being awkward rolling in to a driveway. The C10 had almost 4" of ground clearance.

A sperical joint still wont rotate due to its locked in postion due to the axle. A large rubber bushing will have some give, but like you said it may not last. That is why when I did it we used nearly 4 foot bars. I have read short 2 links have issues at much lower thresholds then long bars. The kid had it on his truck for almost a year, and nothing seemed beat to s***. He had a Vortec 4.3 V6, and drove nearly 20000 miles in the year.
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Old 09-26-2020, 07:50 PM   #17
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Re: A 2-link question-

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Originally Posted by Ziegelsteinfaust View Post
I am not the best at suspension mods as I have always followed preordained formulas, and I could feel what they were supposed to do.

In your last paragraph you pretty much say what is wrong with 2 links. They ride fine, haul weight fine, but the have effectively no side to side articulation. Since the whole rear axle assembly now is effectively like a large sway bar. I described the issue when I pushed the truck quicker down a small twisty road. As i don't remember it being awkward rolling in to a driveway. The C10 had almost 4" of ground clearance.

A sperical joint still wont rotate due to its locked in postion due to the axle. A large rubber bushing will have some give, but like you said it may not last. That is why when I did it we used nearly 4 foot bars. I have read short 2 links have issues at much lower thresholds then long bars. The kid had it on his truck for almost a year, and nothing seemed beat to s***. He had a Vortec 4.3 V6, and drove nearly 20000 miles in the year.
I have wanted to respond w/this info but needed to wait until I had the images to back up what I'm saying. A spherical joint will work w/o bind (within limitation) in a 2-link/Billy-Bar arrangement to allow some ability to articulate. No, not as much flexibility as a 4-bar but definitely movement w/o bind vs. a standard rubber or Poly bushing.

I set up a jig on my fab table to lay out the parts for the test:

*The front hangers are @ 42" for the inner flange (outside width of my table). That should be close enough in the range of truck rails give or take.
*My '99 has the leafs @ a 51" center-line width & this set-up put them @ 47" which made it easier to set-up for the pics.
*I used 4' All-thread @ the front hanger flanges to help keep things aligned & square above the table surface.
*The inner flange of the front hanger brackets were tacked to my fab table to keep the lower edge of the brackets from moving/shifting).
*I put 2pcs of electrical contractors Uni-strut behind the center-line of the rear axle dimension (32" from the front hanger bolt to the approx. center of the rear axle tubes on my '99/OBS). The top & bottom of each piece sandwiches the 2x2x.250 wall 2-link bars that were squared to match the front dimensions.
*I added a 48" long piece of 4" structural C-channel used on pallet racking & double clamped it to each sides link/bar. I positioned this C-channel directly in front of the Uni-struts @ axle centerline. This piece was strictly for locking the bars in parallel @ the axle center-line.

These first images give you an idea of the set-up on the table. It's basically replicating the layout as it would be installed in place of a leaf-spring set-up.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.

Last edited by SCOTI; 09-26-2020 at 08:10 PM.
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Old 09-26-2020, 07:55 PM   #18
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Re: A 2-link question-

In these images, I raised the right side w/a floor jack & took the measurements there.

In the first image w/the tape measure, I took the measurement @ the bottom of the side getting raised when I could start to see daylight between the bottom of the opposite side where it was touching a piece of angle I had the link bars resting on since they're wider than the table.

The 2nd image w/the tape measure is when the housing of the spherical joint was almost @ max rotation. There was still some clearance but @ that amount of travel I felt it was clearly functional w/o binding.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.

Last edited by SCOTI; 09-26-2020 at 08:02 PM.
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Old 09-26-2020, 08:01 PM   #19
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Re: A 2-link question-

At that >7" dimension, the opposite side was still making contact w/the piece of angle clamped to the table....
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-27-2020, 01:12 PM   #20
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Re: A 2-link question-

I will say this again. A 2 link is fine if you want to profile, but will leave you short in the turns. The C10 I put nearly 4 foot bars on understeered heavily, and felt like it was pushing the front end straight in harder turns. Yet was perfectly compliant going 90mph or up a normal driveway. This truck was less the 4" off the ground.

There is lots of suspension things I do not know. As I have stated before I followed formulas for handling, and of the nearly 60 vehicles I have owned. Atleast 55 of them I modified suspension wise. Either lowered, got more travel out of, and or handled better for the street.

Name one OEM manufacturer that used parallel 2 links for any car?

Name one racing class that uses parallel 2 links for handling? We are leaving out drag racing.

Truck Arms angle to the center to give the vehicle IC or instant center. A concept I barely understand. Something parallel 2 links do not do. Which is one of the issues contributing to poor handling at speed, and lots not for get about pinion angle changes here too.

So are Parallel 2 links bad?
Are Brand F I beams bad?
Is Brand F's TTB bad?
Are short leaf springs bad?
Are A-arms superior?
Are long leaf springs always better?

Nothing is all bad or all good. It just has limitations or excells in ways that depending on goals are either ideal or not. Choose wisely, and be honest with your self.

Myself I would only use any parallel 2 link if it was to profile. Otherwise I would get myself killed on any of my other goals because it would hit limitations as I hit the apex of a epic drift.
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Old 09-27-2020, 03:48 PM   #21
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Re: A 2-link question-

I'm not debating if a parallel 2-link is well suited for corner-carving. I have never said or felt it was. We both agree it isn't.

Lets put that one to bed.

I am, w/o doubt, disagreeing w/your statement/declaration that:

Quote:
Originally Posted by Ziegelsteinfaust View Post

A sperical joint still wont rotate due to its locked in postion due to the axle. A large rubber bushing will have some give, but like you said it may not last
The proof is in the pics.

They will have some bind free articulation vs a rubber or poly bushed set-up. The parallel 2-link will always be a compromise but that doesn't mean it can't be improved if one chooses to use the set-up.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 09-27-2020, 05:16 PM   #22
Ziegelsteinfaust
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Join Date: Dec 2012
Location: Temple City
Posts: 3,558
Re: A 2-link question-

Hook it to a car, and watch lack of instant center throw a big curve ball your way.

The OP wants a clean look for profiling, and something that works for cornering. To how much, and what state of tune. I am not sure. But he did describe taking it through the twisty's for fun. Yes you rear end rotates along its suspension access, but that is effective for entering or exiting parking lots. Which let's be honest is a very important part of vehicle construction. Having had 3 vehicles that getting in a parking lot was tantamount to crossing the Rubicon. The OP will have a roughly 4000 pound steel, and rubber beast with a as of yet unstated amount of HP. It will live in a dynamic environment where it can, and will be trying to go in up to 4 directions under sprited driving.

I am a function over form guy, and I am the guy with a $7000 motor in a $500 truck or car. Also nearly 30 years ago I read everything I could on Smokey Yunick. So I took to heart on how to modify crap to precision levels. I dated a girl who's dad+uncle were involved in the Baja races, and used to race stock trucks in the Baja in the late 60's early 70's. Which further taught me how to polish a turd to the high luster.

Which is still to this day what I enjoy most about my stupid projects. How far can I polish a stock turd, and get pretty extreme handling out of it to shame people with water cooled credit cards. Over the last 10 years it has gotten alot harder to beat them, but hanging on there ass like a hemeroid still produces the desired results. Of course the diameter of my testicles may have alot to do with how far over the edge I have taken it, and proved my vehicles relevant. Or I have what leading doctors call a death wish. Plus maybe they just can't drive. You can put my mom in a Ferrari, and I will still be 2 minutes atleast a lap ahead of her in a Geo Metro easily. Either way the predictable handling I had from dialing in the suspension worked, and I only wrecked once. Luckily it was over a berm at 60mph on the Glendora Mountain Road, and I flew into the water. Then I had to swim nearly a 1/2 mile to find a place to climb out. Still with a slightly hurt back in a rough California winter. I have gone backwards off the road quite a few times, and had nothing worse then a dented gas tank.

Which is why I have a fetish for LT1 350's, light duty 3/4 ton trucks, 106 lsa cams, suspension seats, long leaf springs, long shackles, and or leaf spring sliders. It allows me to polish turds to the highest degree I am capable, and leave me enough wiggle room.

Not to get in the way of my other fetish's of AK47's, blondes, potatoes at every meal, anything com-bloc or Russian, and wearing either boots or flip flops. I don't even own shoes anymore.

In two of my previous posts I said I used nearly 4 foot bars to good effect with rubber bushings for the kids truck. Getting in, and out of a parking lot was not a issue. Taking corners at a spirited clip was. The suspension would "load" up, and cause serious understeer issues. Where it felt like the truck no longer wanted to turn or change direction, and nearly plow the front end straight ahead. That was at well under 50mph. I took my dirt road bomber truck through there at over 60mph with the AT tires being my weakest link on street traction.

I am referring to dynamic loads, and this is where parallel 2 links go off the reservation fast. Such as driving spirited down a twisty road. Not out for a cruise where they work fine. There is tons of info out there to read on how, and why decisions of design don't work. You have to weed to the B.S., and the guys who will spend $10,000 for no advantage in the way they really drive or can drive.

I have never claimed to be a suspension designer, but I listen to mistakes/lessons learned before me the best I can.

Or atleast the above is based on my readings of suspension design, and things I have read on other forums for opinions. Plus things I experienced first hand, and info I was given first hand by some racers.

We have a wealth of info at our finger tips on how to build stuff. Which has taken my unimaginative self to greater heights of near death experiences. That is if you don't look at the boobies instead.

The parallel 2 link is to limited in ways I only barely understand to bother, and combined with the cost typically. Unless profiling is the goal, and it will be stuck to that goal. For the same effort he could fab in a parallel 4 link which would be effectively just as hidden, and actually not be fraught with compromise. For only a few more dollars. Or go with a factory TA set-up or engineer his own by following the outline the factory already laid out. Its only metal not Solent Green.
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Old 09-27-2020, 05:41 PM   #23
SCOTI
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Location: DALLAS,TX
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Re: A 2-link question-

Quote:
Originally Posted by Ziegelsteinfaust View Post
Hook it to a car, and watch lack of instant center throw a big curve ball your way.

The OP wants a clean look for profiling, and something that works for cornering. To how much, and what state of tune. I am not sure. But he did describe taking it through the twisty's for fun. Yes you rear end rotates along its suspension access, but that is effective for entering or exiting parking lots. Which let's be honest is a very important part of vehicle construction. Having had 3 vehicles that getting in a parking lot was tantamount to crossing the Rubicon. The OP will have a roughly 4000 pound steel, and rubber beast with a as of yet unstated amount of HP. It will live in a dynamic environment where it can, and will be trying to go in up to 4 directions under sprited driving.

I am a function over form guy, and I am the guy with a $7000 motor in a $500 truck or car. Also nearly 30 years ago I read everything I could on Smokey Yunick. So I took to heart on how to modify crap to precision levels. I dated a girl who's dad+uncle were involved in the Baja races, and used to race stock trucks in the Baja in the late 60's early 70's. Which further taught me how to polish a turd to the high luster.

Which is still to this day what I enjoy most about my stupid projects. How far can I polish a stock turd, and get pretty extreme handling out of it to shame people with water cooled credit cards. Over the last 10 years it has gotten alot harder to beat them, but hanging on there ass like a hemeroid still produces the desired results. Of course the diameter of my testicles may have alot to do with how far over the edge I have taken it, and proved my vehicles relevant. Or I have what leading doctors call a death wish. Plus maybe they just can't drive. You can put my mom in a Ferrari, and I will still be 2 minutes atleast a lap ahead of her in a Geo Metro easily. Either way the predictable handling I had from dialing in the suspension worked, and I only wrecked once. Luckily it was over a berm at 60mph on the Glendora Mountain Road, and I flew into the water. Then I had to swim nearly a 1/2 mile to find a place to climb out. Still with a slightly hurt back in a rough California winter. I have gone backwards off the road quite a few times, and had nothing worse then a dented gas tank.

Which is why I have a fetish for LT1 350's, light duty 3/4 ton trucks, 106 lsa cams, suspension seats, long leaf springs, long shackles, and or leaf spring sliders. It allows me to polish turds to the highest degree I am capable, and leave me enough wiggle room.

Not to get in the way of my other fetish's of AK47's, blondes, potatoes at every meal, anything com-bloc or Russian, and wearing either boots or flip flops. I don't even own shoes anymore.

In two of my previous posts I said I used nearly 4 foot bars to good effect with rubber bushings for the kids truck. Getting in, and out of a parking lot was not a issue. Taking corners at a spirited clip was. The suspension would "load" up, and cause serious understeer issues. Where it felt like the truck no longer wanted to turn or change direction, and nearly plow the front end straight ahead. That was at well under 50mph. I took my dirt road bomber truck through there at over 60mph with the AT tires being my weakest link on street traction.

I am referring to dynamic loads, and this is where parallel 2 links go off the reservation fast. Such as driving spirited down a twisty road. Not out for a cruise where they work fine. There is tons of info out there to read on how, and why decisions of design don't work. You have to weed to the B.S., and the guys who will spend $10,000 for no advantage in the way they really drive or can drive.

I have never claimed to be a suspension designer, but I listen to mistakes/lessons learned before me the best I can.

Or atleast the above is based on my readings of suspension design, and things I have read on other forums for opinions. Plus things I experienced first hand, and info I was given first hand by some racers.

We have a wealth of info at our finger tips on how to build stuff. Which has taken my unimaginative self to greater heights of near death experiences. That is if you don't look at the boobies instead.

The parallel 2 link is to limited in ways I only barely understand to bother, and combined with the cost typically. Unless profiling is the goal, and it will be stuck to that goal. For the same effort he could fab in a parallel 4 link which would be effectively just as hidden, and actually not be fraught with compromise. For only a few more dollars. Or go with a factory TA set-up or engineer his own by following the outline the factory already laid out. Its only metal not Solent Green.
I'm done.
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Old 09-27-2020, 06:50 PM   #24
Ziegelsteinfaust
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Join Date: Dec 2012
Location: Temple City
Posts: 3,558
Re: A 2-link question-

I was not trying to argue, but I dont want the OP to have issues for being cheap. With out understanding on a basic level the issues he can create. Which hopefully would spur a interest to learn why or how and dial in his selections to his reality.
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Old 10-05-2020, 02:14 PM   #25
Low Elco
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Join Date: Apr 2003
Location: Indep, MO
Posts: 5,893
Re: A 2-link question-

Sorry for the friction, Fellas! I was just looking at the basic bits and wondered, why not? I'm actually eyeing a 67 rear and t/a setup. Redrill axles, a posi and wide drums that I have on hand, 3/4 ton calipers up front. Wha-la, cheap narrowed rearend! Not trying to be cheap, as much as I kinda wanted to try a bit of fab work. That being said, it ain't like I can pony up for the QA1 kit anytime soon. Truck will be getting a 5.3/4l60 with a BTR stage 2 truck cam that is on hand. I have a 67-72 t/a xmember to mod/use to mock up. I'm also considering Z'ing the front. We'll see, I took in a 67 GMC to finish out over the weekend that'll take me a bit to deal with, so I've got time to ruminate.
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