LanceD

anyone think of doing a 4 link suspension in the rear for pulling or drag racing? I want to do one for off roading, but not sure how it would act drag racing or pulling, also towing would be a concern too.

Eskimo

it all depends on how you setup the links on how it behaves.

Cowhand

A three link would work better, but unfortunately the fuel tank is in the way. The challenge with 4 linking the rear is triangulating the links to keep the axle centered. Either that or you'll have to run some kind of panhard rod.

Take a look over at pavementsucks.com, rear 4 link has been

Now if you went to a fuel cell in the bed......I'd 3-link it.

turbo thom

Cowhand.........Why is that a pain. The panhard bar is just part of the 4 link system.

And to 3 link the rear, what would replace the springs? Air bags or coil overs?

..PT..

Cowhand

You can do coils, coil overs or air bags with the 3 or 4 link. The sweet set up with a 3 link would be 1/4 ellipticals, but I haven't seen anybody do them for a while. To get a coil over with decent travel in you'd have to go through the bed for the mounts.

The panhard bar is a pain because it somewhat limits articulation, and there isn't alot back there to anchor a bracket to. The rear panhard set ups I've seen usually have a frame anchor that hangs down behind the rear axle. The trick is to get the panhard rod as close to horizontal as possible at ride height so that the axle isn't pushed out to one side when the rear compresses. Kelderman has a bagged 4 link on their website, you can see what they did for a rear panhard rod. A little too busy for me.

There's actually a lot to it as far as getting the angles right so that the suspension articulates well, stays under the truck, and doesn't squat under power.

I've look at it and talked to Don Thuren at length about it, and I figured out it's cheaper and less trouble to go with a quality rear spring pack and a good shock.

CTD NUT

There are different methods of 4 link systems.....some are technically a 5 link system - these are the systems that require a track bar or panhard bar. The best 4 link rear systems for off road use do not use the 5th link track bar.....the top links are triangulated to the center of the axle which eliminates the need for the track bar and allows for perfectly even articulation side to side. The problem is that the rear of a Dodge has the fuel tank directly in the way for the driver side top link to cross over to the center of the axle.

Also, either the 3 or 4 link would require you to use something to replace the leaf springs.....there isn't much point in keeping the leafs when going through all the work to fab a 4 link.

IMO, I would not suggest the 3 link on the rear of a truck like this. It might work well for drag racing but you will see too much lifting of the rear. I know the instant center can be adjusted to compensate but you would have to have adjustable link mounting brakets to allow for this. It will be easier to develop a more neutral system with less trial and error on a 4 link that will make for a rear suspension that will be much better at multi tasking in a variety of applications instead of working well at just one thing.

If you didn't want to go with the fuel cell in the bed, the 4 link with the track bar would probably be the better way to go to have a system that performed well in several applications.

LanceD

how big of a fuel cell do you think I could fit where the spare tire goes without it hanging down past the bottom of the bumper? I have a 3 inch body lift too.

12vchevydually

We have a 4 link,front and rear on our Camaro that we sled pull with. Its is not set up to artulicate but is shure does good with the sled behind it, and I am shure it would work good at the strip too. We built a sub-frame under the camaro's uni-body, and we used coil's front and rear, with a panhard rod.

CTD NUT

I'm sure you could easily tuck a 30+ gallon custom tank or cell in the spare tire location.

LanceD

you sled pull with a camaro? i gotta see that, you got any pics?

12vchevydually

Its not mine, Its my friends, I am waiting on the Image to be Approved.

LanceD

I plan on doing a link setup with some hefty coilovers, but I was going to add some air bags about 1/4 of the way down the links to help keep it level for towing and such.

Artsi_L

Here are few pics of a race truck I took some months ago at local track event. As I wandered around the pits, some other trucks had 3rd member supporting the rear axle as well.
I've studied basic principles of a regular 4-link suspension. That encouraged me to engage the team mech in a discussion over 3rd member settings. He confirmed to me that it'll help out acceleration out of the apex by making it harder for the back end to break loose once hammer is dropped.

Any 3- or 4-link setup will only provide a 'bite' only for a short duration, but it's enough to make the difference.
If we dial it in to present a strong influence in a 'hook up', time duration of desired action will shorten - and vice versa.

This setup runs with leaf springs.



Here are rest of the pics.
Make note of the engine, if memory serves me right, it is a 14 liter unit (i.e. N14 or a 855). They are allowed to use single turbocharger only. That Holset will push 4.0 bar gauge pressure regardless of this handicap.

Sorry for coarse picture quality. Web hosting does not accept high resolution pictures due to bandwidth, so I had to bring down resolution quite a bit from the original shots.











Here's a cold start for you

HOHN

I wish there was a Y-link setup for our trucks. This would totally eliminate axle wrap and give you more flexibility than a 4-link.

Now if you want a LOT of flex, you can triangulate the Y-link setup. A friend has triangulated Y-link setup on his jeep. It's made by a local Cheyenne fabricator who runs http://www.tntcustoms.com I took the pic above from their website.


Conrad, don't you think you could make a 3-link setup like the above pic work on our trucks? Couldn't you mount the Panhard bar somewhere beside where the tank is?

CTD NUT

The Panhard link fits in the rear of a Dodge.....it is the 4 link with the top 2 links triangulated to the center of the diff that does not fit in a Dodge with the fuel tank in the stock location.

This is the style of 4 link I'm referring to that does not fit: