Info needed for 4 link geometry

[Tri5Nerd]

Using Hotrodrookie post:
http://67-72chevytrucks.com/vboard/s...d.php?t=348682
I would some help with setting my Triangluated 4 link up.
My truck is a 55.2 Task Force series, shockwaves for the 4 link.
The wishbone I have is 24" long from center of heim joint, 27" wide from outside of bushings.

How long should my parrallel bar be? using Twisted Minis drawing I would try to get 45% between the lower bar and the wishbone.
What other measurements would I need to set this up correctly?

Thanks
Tri5

[1Bad62Pro/Street]

Yea,
I want a 4 link set-up on my 62.
So far I don't remember anyone on here who has a 4 link set-up on 1960-1962 frames here on the forum. I probably wind up just having ladder bar set-up with floaters.


http://www.competitionengineering.co...s/chassis2.asp

http://www.truckinweb.com/tech/suspe...dup/index.html

http://www.toodoc.com/4-link-suspension-ebook.html

New 55-57 Triangulated 4-link
http://www.heidts.com/

[joe231]

I believe, but could be wrong, you are going to want your 2 straight bars the same length as your wishbone, otherwise they will be traveling in different arcs and fighting each other, and your pinion angle would change through out travel. your wish-bone should have the required angle built in so the other 2 bars should be parallel to your frame and 90 degrees to your rear differential.

technically a wish bone and 2 lower links is a 3 link, not a triangulated 4 link

[Tri5Nerd]

Originally Posted by joe231

I believe, but could be wrong, you are going to want your 2 straight bars the same length as your wishbone, otherwise they will be traveling in different arcs and fighting each other, and your pinion angle would change through out travel. your wish-bone should have the required angle built in so the other 2 bars should be parallel to your frame and 90 degrees to your rear differential.

technically a wish bone and 2 lower links is a 3 link, not a triangulated 4 link

You're correct about the wishbone being a 3 link. I thought that the parrallel bars should be longer, plus I'll be running air bags.

Tri5

[joe231]

so you are gonna run a 3 link, or are you planning on running a parallel 4 link AND a wish bone, guess I'm confused..

there are some on here that are very knowledgeable on suspension geometry.....maybe they will chime in.

[Tri5Nerd]

Originally Posted by joe231

so you are gonna run a 3 link, or are you planning on running a parallel 4 link AND a wish bone, guess I'm confused..

there are some on here that are very knowledgeable on suspension geometry.....maybe they will chime in.

It is a 3 link, the wishbone and 2 parrallels bars.

[hotrodrookie]

Today I was on the phone with tech support at Art Morrison and the guy said it really doesnt matter how long or short the bars are from 18 to 27 inches, it just makes the angles determening the instant center more drastic with any adjustment. The longer the bars, the less drastic the change, the shorter the bars, the more drastic the adjustment. So Im sure the same rules apply to the three link wishbone that you just draw out you bars from a side view of the car and choose where you want your instant center. Hope that helps. Im new to suspension so any one correct me if Im wrong.

[abadsvt]

I have not setup a 3 link before but the longer the bars are the less pinion angle will change also. What i would do is mock up your rear end in a fixed location at ride height and then see how long of bars you can go. I would recommend having the lower bars paralle to the ground at ride height so that will affect how long the can be becaue of the brackets. Nathan told me one time that you rarely ever can have a perfect suspension setup and that its all about compromises. If you try to do one thing it affects another and so on. Good luck and i am no suspension expert so maybe twisted or nate will drop a line in!

Josh