Triangulated four link - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Suspension - Brakes - Steering
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-22-2005, 05:51 PM
41willys's Avatar
Blowin' it
 
Last wiki edit: Choosing a trailer
Last journal entry: Running again...
Last photo:
Join Date: Aug 2002
Location: Katy, Texas
Age: 39
Posts: 417
Wiki Edits: 11

Thanks: 0
Thanked 0 Times in 0 Posts
Triangulated four link

I seem to have an issue I can't figure out. I have a narrowed 9" with a triangulated four link. When I goose the go pedal lightly (doesn't take much) the rear of the car seems to want to shift to the right. I have reinspected all the mounting locations and rod ends, with nothing loose.

Could I need to take some turns out of the one side of the links? Anyone run into this?

The rear end is centered side to side and front to back exactly...


Jason

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-23-2005, 09:21 AM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,196
Wiki Edits: 0

Thanks: 0
Thanked 20 Times in 19 Posts
Are both bottom links and both top links the same lenght, Mounted in the same place with relation to the X, Y, axis? You might be jacking in some rear steer.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-23-2005, 09:51 AM
41willys's Avatar
Blowin' it
 
Last wiki edit: Choosing a trailer
Last journal entry: Running again...
Last photo:
Join Date: Aug 2002
Location: Katy, Texas
Age: 39
Posts: 417
Wiki Edits: 11

Thanks: 0
Thanked 0 Times in 0 Posts
Hey thanks for responding. Yes, both bottom links are the same and both uppers are the same. Obviously the tops are about 1/3 of the bottoms.

When welding in the brackets I was very worried about making everything even. Measure - measured - measured until i made myself go crazierer.

Whats got my attention is how the car drives straight as an arrow, but when goosed it feels like the rear diff is trying to swing, causing the back of the Willys to kick to the right for a split second. It may just be the tires letting loose which it does.

I have noticed that when placed in reverse, you can physically see the tires kick.

Something has got to be loose somewhere, and I am overlooking it.


PlEaSe HeLp!!!!


Jason
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-23-2005, 12:03 PM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,196
Wiki Edits: 0

Thanks: 0
Thanked 20 Times in 19 Posts
Are both tires spinning or just the righ rear? Breaking traction on the right rear only will give you feeling as the car loads the left rear. Try placing a bunch of weight just behind the RR tireas far R as possible. Test again.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-23-2005, 12:14 PM
41willys's Avatar
Blowin' it
 
Last wiki edit: Choosing a trailer
Last journal entry: Running again...
Last photo:
Join Date: Aug 2002
Location: Katy, Texas
Age: 39
Posts: 417
Wiki Edits: 11

Thanks: 0
Thanked 0 Times in 0 Posts
Yeah their spinning, its a detroit locker, and the locker is working...can see both wide black rubber its leaving.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-23-2005, 01:03 PM
Member
 
Join Date: Sep 2005
Location: texas
Posts: 48
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 41willys
I seem to have an issue I can't figure out. I have a narrowed 9" with a triangulated four link. When I goose the go pedal lightly (doesn't take much) the rear of the car seems to want to shift to the right. I have reinspected all the mounting locations and rod ends, with nothing loose.

Could I need to take some turns out of the one side of the links? Anyone run into this?

The rear end is centered side to side and front to back exactly...


Jason
Try this
Jack the rear of the car up and put jack stands under the frame just were the lower front arms mount. Then let the rear axle down until it hangs free. Then move over to the side of the car, grab the tire/wheel and push and pull it hard. If it moves any then you have something loose! The axle should not move side to side at all.
If you've had this problem since you put it together you might not have enough cross angle in you four bar. Thats easy enough to fix without cuttin and welding new mounts in.
All you would need would be a diagnal link. You could check out any chassis shop online for a kit usually $100 or less and is make to fit you combo.
Hope this helps
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 09-23-2005, 01:19 PM
Member
 
Join Date: Sep 2005
Location: texas
Posts: 48
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 41willys
I seem to have an issue I can't figure out. I have a narrowed 9" with a triangulated four link. When I goose the go pedal lightly (doesn't take much) the rear of the car seems to want to shift to the right. I have reinspected all the mounting locations and rod ends, with nothing loose.

Could I need to take some turns out of the one side of the links? Anyone run into this?

The rear end is centered side to side and front to back exactly...


Jason
Also you might not have the 4 bars loaded correctly. Since you have
a narrowed 9" with a triangulated four link I would think you have rod ends on tubes. You will have to tighten the upper bars to get them to pull on one another. Thats kinda hard for me the explain but I'll try. You see the upper bars are what keep the axle from shifting from side to side and there needs to be tension accross them.
Do like I said before about jacking the car up but dont let the axle hang keep it at ride hight. Then working under the car tighten up on the upper bars equally untill there is no slack. Then if the pinion has dropped down and pointed more to the ground your triangulation is wrong. Then I would readjust it back to where the pinion was where it started and put on a diaganal link.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 09-23-2005, 09:31 PM
Member
 
Last wiki edit: Vacuum brake bleeder set up
Join Date: Nov 2003
Location: So Cal
Posts: 1,245
Wiki Edits: 8

Thanks: 0
Thanked 0 Times in 0 Posts
Are the lower control arms parallel (when viewed from the top)?
What angle are they at (when viewed from the side)?
Do you have microsoft excel on your computer (serious question)?
What spring rate are you using?
How far appart are the springs/coilovers at the axle?
Do you have a rear anti-roll bar?
What are you using as link ends?

I'm sure I am missing a few questions...
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 09-24-2005, 08:37 AM
Member
 
Last photo:
Join Date: Aug 2005
Location: Fort Worth, Texas
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
4-link/same problem

I'm following with interest. I installed a triangulated four link with transverse leaf from Industrial Chassis in a 57 chev PU, ZZ4/9"posi rear. I had the same problem you're having. IC had me change the rear spring, no help. They said sway bar wasn't needed. Their final say was that I didn't get it square when I installed it- I'm pretty careful about those things. I had a local shop look at it- they couldn't explain it either, certainly everything was good and tight. Bill
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 09-24-2005, 12:16 PM
41willys's Avatar
Blowin' it
 
Last wiki edit: Choosing a trailer
Last journal entry: Running again...
Last photo:
Join Date: Aug 2002
Location: Katy, Texas
Age: 39
Posts: 417
Wiki Edits: 11

Thanks: 0
Thanked 0 Times in 0 Posts
The rear diff housing is center side to side and front to back where it needs to be. The lower links are parallel to each other. I do have excel??? I do not know the spring rate. The people I purchased from ordered everthing to what I was using it for. I would have to go measure the distance between the coil overs. I do not have an anti-roll bar, and I am using thread in rod ends.

Jason
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 09-24-2005, 12:34 PM
Member
 
Last wiki edit: Vacuum brake bleeder set up
Join Date: Nov 2003
Location: So Cal
Posts: 1,245
Wiki Edits: 8

Thanks: 0
Thanked 0 Times in 0 Posts
The reason I asked if you had excel is that I wrote a little spreadsheet that will tell us a bit about your suspension. See this link:
http://mysite.verizon.net/triaged/fi...arLinkV3.0.zip

My *guess* is that what you are feeling is "torque lean". The driveshaft torque will cause the axle to want to lift the right rear (and plant the left rear) while the body will want to dip on the right side. Moving the springs in closer to the center of the axle will cause this to be amplified because they have less leverage to resist the torque. The anti-roll bar in the rear will help counteract this. Also if the lower control arms are not parallel with the ground (when they are parallel to each other) the rear axle will want to "steer" as the body rolls. The combination of these things *I think* would be enough to make it feel funny on acceleration.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 10-21-2005, 04:00 PM
41willys's Avatar
Blowin' it
 
Last wiki edit: Choosing a trailer
Last journal entry: Running again...
Last photo:
Join Date: Aug 2002
Location: Katy, Texas
Age: 39
Posts: 417
Wiki Edits: 11

Thanks: 0
Thanked 0 Times in 0 Posts
Update:

I have solved the problem. I tried everything I could think of, and what you all suggested. Everything was tight, everything was set correctly. I tried suspending car in air and letting rear end hang, but no movement.

Again, this is a triangulated 4-link, and I went a got a new Competion Engineering weld in diagonal link. Finished setting everything up today. Guess what, no more of the car trying to jump sideways. Called C.E. and they told me that the torque was too much for the 4-link to hold by itself.

I guess next time I will just run a regular 4-link with a diag. link.

Jason
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 10-21-2005, 05:29 PM
Member
 
Last wiki edit: Vacuum brake bleeder set up
Join Date: Nov 2003
Location: So Cal
Posts: 1,245
Wiki Edits: 8

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 41willys
Update:

I have solved the problem. I tried everything I could think of, and what you all suggested. Everything was tight, everything was set correctly. I tried suspending car in air and letting rear end hang, but no movement.

Again, this is a triangulated 4-link, and I went a got a new Competion Engineering weld in diagonal link. Finished setting everything up today. Guess what, no more of the car trying to jump sideways. Called C.E. and they told me that the torque was too much for the 4-link to hold by itself.

I guess next time I will just run a regular 4-link with a diag. link.

Jason
That is one way to solve the problem.

To explain why your solution worked:
What you did was to over constrain the rear axle. That is to say that the triangulated links already held the axle laterally and you now added a 2nd lateral restraint.

What this does is cause the links/brackets to have to "flex" in order for the axle to articulate (or the body to roll).

In essence your solution was the same as installing a large diameter anti-roll bar.

FWIW a "regular" (parallel and equal length links) 4-link and Panhard bar would have exactly the same problem as your triangulated 4-link had. Your problem was not enough roll stiffness to handle the torque of the driveshaft.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 10-25-2005, 04:32 PM
Member
 
Join Date: Sep 2005
Location: texas
Posts: 48
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Fultron
Try this
Jack the rear of the car up and put jack stands under the frame just were the lower front arms mount. Then let the rear axle down until it hangs free. Then move over to the side of the car, grab the tire/wheel and push and pull it hard. If it moves any then you have something loose! The axle should not move side to side at all.
If you've had this problem since you put it together you might not have enough cross angle in you four bar. Thats easy enough to fix without cuttin and welding new mounts in.
All you would need would be a diagnal link. You could check out any chassis shop online for a kit usually $100 or less and is make to fit you combo.
Hope this helps
YOUR WELCOME!
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 10-25-2005, 04:49 PM
Member
 
Join Date: Sep 2005
Location: texas
Posts: 48
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 41willys

Whats got my attention is how the car drives straight as an arrow, but when goosed it feels like the rear diff is trying to swing, causing the back of the Willys to kick to the right for a split second. It may just be the tires letting loose which it does.

I have noticed that when placed in reverse, you can physically see the tires kick.

Something has got to be loose somewhere, and I am overlooking it.


PlEaSe HeLp!!!!


Jason
Quote:
Originally Posted by Triaged
That is one way to solve the problem.

To explain why your solution worked:
What you did was to over constrain the rear axle. That is to say that the triangulated links already held the axle laterally and you now added a 2nd lateral restraint.

What this does is cause the links/brackets to have to "flex" in order for the axle to articulate (or the body to roll).

In essence your solution was the same as installing a large diameter anti-roll bar.

FWIW a "regular" (parallel and equal length links) 4-link and Panhard bar would have exactly the same problem as your triangulated 4-link had. Your problem was not enough roll stiffness to handle the torque of the driveshaft.
ok.....answer me this..........if the diagonal link is in the lower set of bars how does it affect body roll? It doesn't, it will only affect the lateral movement. In a regular 4 link set up to change how the car lauches you adjust the upper bars, the lowers are for tracking mostly, they do not affect the body roll. so by putting the diaginal link in the lower bars it limits the side to side shift of the axle.

He complained of the rear kicking out even in reverse not the body rolling. One thing he left out of his post is that he also had poly urathane bushings instead of rod ends at least thats what he emailed me. I think mostly the poly bushings were giving to much and allowing the rear to move under torque, torque steer!

Still if the triangulated bars were set correctly it shouldn't have had this problem.
Reply With Quote Quick reply to this message

Recent Suspension - Brakes - Steering posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
BROTHERS 4 link for a '49 chevy truck. hiimed Suspension - Brakes - Steering 6 08-25-2013 01:11 AM
Project Journal link not showing up 78novaman Hotrodders Site Suggestions and Help 11 07-23-2005 10:06 AM
Triangulated 4 link help?! jqmile Suspension - Brakes - Steering 14 10-19-2004 10:35 AM
4 link vs. triangulated 4 link. rear suspension bentwings Suspension - Brakes - Steering 4 11-23-2002 01:44 PM
Parallel 4 link or Triangulated 4 link rear ? RonWood Suspension - Brakes - Steering 1 11-13-2002 08:25 AM


All times are GMT -6. The time now is 04:23 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.