3 link or 4?

[Neverdone]

So I am redoing the back of my rat rod. My buddy that started building it, whom I bought it from built the link rods very stupid (no pivot points). Now I am of course redoing it since I am putting on air bags, and I don't want to die. My question was, he built it with a three link, should I keep that or change it to a four? What are the pro's and con's what is necessary if I change it to a four link?

 

[donsrods]

Let's see some pictures of what you have.


Don

 

[Neverdone]

Here is my build thread I have going, You can kind of see what he had going.

http://ratrodsrule.com/forum/showthread.php?t=16828

This is why I am redoing it.

Not very structural as you can see from the bends......

I have since then cut the frame at the rear Z and started rebuilding. Unfortunately I have no pictures of what I have going on currently. I can tell you that the frame in the back is now on a slant instead of straight, and it goes across the top of the rear axle. It starts farther forward, and I put a cross piece half way up the new sides.

 

[Bonehead]

That type of link configuration, (not looking at the rod ends) offers nothing to locate the axle left and right. A triangulated 4 link does that, or, links that will keep the axle from rotating, along with a panhard bar. Look at the front end of a ford bronco 4x4, ( 66-79) and you will see a similar bushing set up as what you have. The difference is the panhard bar and a c bushing to keep the axle from rotating. The mounts will have to be much stronger.

A typical 3 link with a mount on top of the diff. will also have a panhard bar, (making it a 4link)
There are many options, but the main thing you have to do is keep the axle centerd on the frame, and locate the axle so it stays the same on both sides, and does not roatate under power.

 

[rainman]

How much power will you're power plant have? If you're looking to hook up mucho power, go 4 link, 3 link not so much!! IMHO

Having said that since it seems like you'll be redoing the whole thing anyway, why not do a triangulated 4 link?

 

[Neverdone]

How much power will you're power plant have? If you're looking to hook up mucho power, go 4 link, 3 link not so much!! IMHO

Having said that since it seems like you'll be redoing the whole thing anyway, why not do a triangulated 4 link?

Probably the biggest discouraging factor is that I do not know how to set one up. I know you can't just build it how you want and expect it to work right.

I am not ever planning on running mucho power to this thing, right now it has a I6 in it. Some day many moons from now I am planning on putting in a mildly built 5.0 HO engine that I have sitting for it. All done 300-350HP is about the goal. It has a c4 in it now and a 9" with 2:73 highway gears. At some point I would like to ditch those to for 3:55 or 3:73, but that is also down the road.

 

[Sam_Fear]

no panhard '3-link':

 

[Neverdone]

Is that one of your creations or something available for purchase?

 

[Bonehead]

I used a similar one on my son's Jeep, but the "Y" goes the other way. Two connections on the frame, one on the rear end.

 

[rainman]

That type three link is becomming very popular!!
Seems like the one pictured would work better with a heim in the front
for more movement!!! Guess it doesn't have to move that much though!

 

[rainman]

Probably the biggest discouraging factor is that I do not know how to set one up. I know you can't just build it how you want and expect it to work right.

I am not ever planning on running mucho power to this thing, right now it has a I6 in it. Some day many moons from now I am planning on putting in a mildly built 5.0 HO engine that I have sitting for it. All done 300-350HP is about the goal. It has a c4 in it now and a 9" with 2:73 highway gears. At some point I would like to ditch those to for 3:55 or 3:73, but that is also down the road.

Find a late 70's or early 80's impala, measure the upper and lower control arms, study that set-up, and use those ratio's, for length. You don't have to use the exact same length just the ratio's. make sure to keep mounting height the same.
There are several different cars you can use for reference to do this.
I like the set up on the rear of 74 to 79 midsize fords, (t-birds, cougars, torino....) just because I'm very familiar with them!!

Hope this helps!!

 

[bob w]

I built a 3 link with a Watts link for side control for my Fiat. In the "builds" section search for "Fiat" if you want to see pics.
There's a Youtube video of a Camaro with a 4 link and a 3 link set up by Morrison comparing their performance. They are very close in cornering but the 3 link is a bit better.

 

[donsrods]

That 3 link Sam posted a picture of is made by a company called Suicide Doors. We have one in the shop that we originally had under the 39 Dodge, but I saved it when we sold the car off. I MAY use it in my new rpu project, just have to see how it fits.

Here are some pictures of how it looks installed. That flat plate on the back is for an S10 type rear so you can just bolt it on. On this car I will be using an 8 inch Ford, so I can weld tabs on to eliminate that plate. You also need no panhard with this setup.

Don

 

[ratrodz]

check out a ford aerostar van rearend they are setup a lot like that. they have a 8.8 in them you could buy the rearend and bars and just have to make the front brackets

 

[skull]

her

try here,

http://www.thedirtforum.com/4link.htm


all the way at the bottom of this page are some vidios that may help.

http://www.thedirtforum.com/toolbox.htm

Later

 

[Jimmy Wallbanger]

Look at mini truckin

When I messed with mini trucks I got to see alot of crazy link set ups. Look at a mini mini truckin mag or google FBI custom truck parts they have alot. 3 and 4 links are fairly cheap on eBay and a 3 link ladder bar st up would work and handle power with the old school look

 

[Neverdone]

this is kind of where I am right now. I still have a lot of welding to do to get this done.

I saw a kit on ebay for a triangulated four link set up that I think I can modify a little and make work. It has all the rod ends, links, and brackets in it for $200. Might take that route.

 

[LOWANDRATY]

Rear setup

Before you go the Ebay route talk to RPM right here on this site, he makes and sells everything you need, you never know what your getting from Ebay, some china junk maybe ??? here is his add, very nice guy.


" We build T Bucket and Rat Rod chassis parts. From the smallest chassis bracket to a complete rolling chassis. We have a CNC Plasma cutter that will cut up to 1" thick material. We love to do one of special parts.

We also do custom gas tanks, radius rods, straight and drop front tube axles.

Check out the web site. http://www.eztbucket.com/
__________________
Custom made CNC Plasma parts. www.eztbucket.com

Toll Free 855-TBUCKET "

 

[Anarchy]

just my 2 cents. If your going air ride you might wanna try a rear suspinsion and rear end from a crown vic or linc. town car, and you can get several of the things you listed u wanted. higher gear ratio probably in the 3.23 range as i havent seen one with a 3.73 yet, a triangulated 4 link with air ride, all you have to do is fab mounting points on the frame. Oops correction some lincoln mark VII's have 3.73 gears with air ride and disk brakes they are on some of the LSC versions not bill blass.

pros
1- 8.8 easy to upgrade, gears, c clip eliminators ect.
2- disk brakes with out the added cost of converting a 9"
3- air ride- air bags are cheap compared to aftermarket $100ish for rear bags new
4- rear anti sway bar/can be fabbed in
5- total cost, cheap around here i can get a complete rear for around 250 to 350 bucks depending on junk yard and thats with the upper and lower control arms and the bags.

cons
1- 5x4.5 wheel lug pattern sucks if you have a 5x5.5 up front but depending on what front end your using it may actually become an up grade for the front brakes. IE If your running an old ford solid axle speedway has a disk brake kit for around 300 bucks and you can change the lug pattern with it.

hope this helps a little

 

[Neverdone]

Thanks for the advice, but I would hate to ditch a good 9" already installed. Besides that when I bought it from my buddy and started this project, he had already done a disc brake conversion on it as well. To top that off, I already bought the air bags, and have them installed.

But that is very good info to have and if I ever build another RR I will keep that in mind!! Would save a lot of headache in the future.