3-link or 4-link??

[sandking]

With the exception of one more heim, what else is the difference? Supposedly the 4-link is stronger, so why would you want the 3-link?

Also, what is the most common degree of the bend in the trailing arm for a full size Chevy? What are the factors that determine the degree?

Thanks in advance, Joey

[JrSyko]

With the exception of one more heim, what else is the difference? Supposedly the 4-link is stronger, so why would you want the 3-link?

Also, what is the most common degree of the bend in the trailing arm for a full size Chevy? What are the factors that determine the degree?

Thanks in advance, Joey

If you do a search, this topic has been discussed at great lenght before. Good luck!

[mxmobber29]

i personally do not know much about 4 and 3 links but what i do know is from seeing what works if you have 800hp id say go with the 3 link because you still can get axle wrap with a 4link i also believe 3links are easier to make than 4 links. you get more adjustability out of a 4link and thats good but sometimes not. you have to be more involved with a 4link and setup is more crucial. my 2 cents

[tedmales]

i personally do not know much about 4 and 3 links but what i do know is from seeing what works if you have 800hp id say go with the 3 link because you still can get axle wrap with a 4link i also believe 3links are easier to make than 4 links. you get more adjustability out of a 4link and thats good but sometimes not. you have to be more involved with a 4link and setup is more crucial. my 2 cents


you do not get any more wrap with a 4 link vs. 3 link.

[singlehanded]

"i personally do not know much about 4 and 3 links but what i do know is from seeing what works if you have 800hp id say go with the 3 link because you still can get axle wrap with a 4link i also believe 3links are easier to make than 4 links. you get more adjustability out of a 4link and thats good but sometimes not. you have to be more involved with a 4link and setup is more crucial. my 2 cents"

What 800 hp trophy trucks run 3-link?

A four link it the only way to go, for dezert racing.

[Ryan_P]

i personally do not know much about 4 and 3 links but what i do know is from seeing what works if you have 800hp id say go with the 3 link because you still can get axle wrap with a 4link i also believe 3links are easier to make than 4 links. you get more adjustability out of a 4link and thats good but sometimes not. you have to be more involved with a 4link and setup is more crucial. my 2 cents

With a 4 link you get more articulation, because each upper link is independent from eachother.

http://www.race-dezert.com/forum/showthread.php?t=4050&highlight=lower+links

-Ryan

[WoodyW]

if I remember correctly Collins 3 seater has your everyday standard wishbone/ 3 link...

[ntsqd]

if I remember correctly Collins 3 seater has your everyday standard wishbone/ 3 link...


And it's age is? 3 links were common b4 4 links became common. I stood on the back of that truck using it's battery to jumpstart another truck, but it was dark and I don't recall what it has.

The only real difference I see btwn the two is whether you want a staionary Roll Center, or one the moves relative the angle of the upper arms. There has been plenty of discussion on this topic in other threads to re-hash it yet again.

[Ryan_P]

Hmmm......Robby Gordon builds all of his TT's with a four link, and they have around 7-800hp. Including his own and Chet Huffmans, shown on the pictures below.
http://www.desertrides.com/features/vehicles/gordonTT/images/DSC02352.jpg
http://www.race-dezert.com/skunkz/chet_huffman/47.jpg

Porter also builds their trucks with 4 links.
http://www.desertrides.com/features/vehicles/hermanTT/images/DSC03549.jpg

Newline, Camburg, Geiser, also to name a few more.

Also, I don't understand how you can get axle wrap out of a 3 link and not a 4? Considering they are stationary on the top and bottom, therefore they do not twist.

-Ryan

[WoodyW]

must be at least 5-6 yrs now right thom? wasn't making a judgment call...only an observation that there are in fact tt's with three link rear suspension.

[mexracer10]

Dont think it a age thing both have been used for ever and a day just what ever number you like 3 or 4?

[Ryan_P]

must be at least 5-6 yrs now right thom? wasn't making a judgment call...only an observation that there are in fact tt's with three link rear suspension.

Well, I know of a couple trucks that ran 3 link rear suspension. One of which is the Danahoe truggy and TT.
http://race-dezert.com/skunkz/donahoe/57.jpg

Larry Roselor's prerunner also runs a 3 link, built by C&D Fabworks. Also built by C&D, Chris and Danny's old ford has a three link, along with their ranger featured in off-road and currently for-sale.
http://www.jordansrealm.com/featuredrides/cnd/cnd155.jpg
http://www.jordansrealm.com/featuredrides/larry/cnd45.jpg


I know they are not currently HUGE maufacturer, but ESB Mike builds three links as well, on his truck and The Piece. Solo Motorsports is also another shop that utilizes 3 links.

-Ryan

[ntsqd]

must be at least 5-6 yrs now right thom? wasn't making a judgment call...only an observation that there are in fact tt's with three link rear suspension.

True. I was thinking that you're more likely to find a 3 link in an older truck than in a newer truck. That's been my observation anyway.

There is more tuning possiblity in a 4 link re: Roll Center vs. CG, but if a 3 link can do the job to your satifaction then why add the complexity of a 4 link?

[Ryan_P]

Also something to add, most people that do infact build 3 links, their shocks are mounted above the center line in the lower link, while people who prefer 4 links, their shocks are mounted evenly or below the centerline. This might have to do with the articulation issue, that 4 links get more articulation than 3. ????

-Ryan

[Josh_K]

NO, three links are easer to layout and are more simple. I seems your right about your observation about where shocks mount, but I dont think it applies.

In my experience, if you are linking a framed truck, it is easer to go with a 3 link. If you are linking a space frame design and can get the links to mount further out than the frame would allow, a 4 link makes sense.

It is possible and totally doable to link a framed truck, but the angel of the upper links is vary close and induces allot of shear and bind. 3 links welded solid and can deal with this binding a shearing better and induce less strain into the frame.

Josh

[ChuckH]

If you run heims on both ends of the arm you should have the shock mount a bit below the centerline ( with a 3 or 4 link) it will roll to the side and beat the he11 out of the heims from twisting them if you have it above, if you look at the last two pics they only have a heim on one end so they can get away with running the shock above the centerline

[Josh_K]

You’re correct; the 3 link is mounted using nylitron bushings, so most people use these bushings to mount the forward end of the lower links. In my case it’s the simpleness factor.

[Ramsey_ElWardani]

If you run heims on both ends of the arm you should have the shock mount a bit below the centerline ( with a 3 or 4 link) it will roll to the side and beat the he11 out of the heims from twisting them if you have it above
OK!? So that applies under compression. Have you thought about rebound? The opposite is true. Damn! Now what do you do?

[ChuckH]

Now what do you do?

Be sure and wear a tinfoil hat on your helmet, if you really want to play it safe wrap your steering wheel in tinfoil also, i thought everyone knew tinfoil protected people from bad things.

Much less force on rebound, its mostly in the shock since that were the spring is pushing down so its mosty isolated, except for the weight of the rear end.

[Just4Fun]

Well a 3 link will get more duck walk, but a 4 link will control it better. It is up to personal preference. Every shop is different. Just like were you mount the shock mount on the trailing arm, on top, above centerline, centerline or below. Just like the front pivot; bushing, uniball or heim. They all work, but there is no CORRECT way of doing things.
The downfall to big horsepower and big suspension is that you have a slip joint. Weather it be in the tranny or the driveshaft you have 800hp going and trying to align the gears...with tends to blow things apart. We had Culhane build us a billet tail shaft w/ 2 sealed bearings instead of the stock crush sleeve and bushing because it kept blowing out. This also depends on your driveshaft length and if you are running a carrier bearing.
Here is a picture of our truggy, it is a 3 link only because of how they had to be mounted. The frist arms started out w/ heims front and rear and shocks set up at centerline. Soon found out that you needed something to control the trailing arm; also these arms are really short. So the new ones have a uniball in the front and the shocks are placed below centerline. Remember there is no set WAY, just depends on who you talk to. The rear is limited at 34" and works perfect.

[tre5]

An advantage of a 4 link is that you can keep spare upper links on the truck. Just in case you bend one and don't mess anything else up. Also if you are doing a 3 link make sure that the heim on the wishbone is mounted correctly on the rear end. You want the bolt running vertically. The heim is not strong enough to be mounted the other way and will eventually blow out.

[tedmales]

Also if you are doing a 3 link make sure that the heim on the wishbone is mounted correctly on the rear end. You want the bolt running vertically. The heim is not strong enough to be mounted the other way and will eventually blow out.

that has been discussed too, not everybody agrees with that.

[racer_dude]

i dont see how you can get more articulation out of a 4 link than you could a 3 link... you have 2 points on the top of the rear-end that are spaced away from the center of the rear-end, how can they work independently if you try to duck walk it one side goes up, and the other has to go down to adjust for the other side of the rear end falling. with a 3 link it is mounted in the center and doesnt have to worry about 2 lengths that are not center..... also, how many times have you adjusted the heims on a 4 link after the original set-up?

i think the whole 3-4 link is preference... the first pre-runner we built was 3 linked (nick baldwin owns it now) and the bronco we have now is also 3 linked. ranger had the frame cut at the back of the cab, and the bronco has the full frame... our protruck has a 4 link and after the first test has been set at the exact same set-up and hasent been touched...

mike ruane's 7 (team orbit) truck uses a 3 link that just got converted to a uniball

[Josh_K]

*************SENSORED*******************

This post was sensored and deammed usless information by the allmighty powers to be. Let this be a warning to all not to thread jack!

[matt_helton]

oh no, its the dreaded bolt direction discussion......im having deja-vu.

[ntsqd]

I think the bolt should go front to back. That way if the nut falls off the bolt won't disappear and you can then use the loose one behind the steering wheel to secure it.

3-4 vs articulation would be entirely dependent on the geometry of the links. Can not catagorically say one design will articulate better than the other.

[V8Ranger]

OK!? So that applies under compression. Have you thought about rebound? The opposite is true. Damn! Now what do you do?


On rebound the shock (spring) still pushes down on the lower link and rear end so you have the same scenario as you do in compression. If the tire/rear end was "pulling" on the shock then you would be correct but that's not the case.