Coilover question

[broncomikem]

I bought a bronco with coilovers on all 4 corners. I finally had the opportunity to wheel it and really noticed that when dropping off a ledge at a angle, it wanted to unload on the rear up hill corner and felt like it was wanting to go over, I have always wheeled in a coil front/ leaf spring rear bronco and never felt the rear unloading like that. It is 4 linked in the rear with 16" Fox coilovers, 3 linked front with 12" Fox coilovers, has a antirock sway bar in the rear. I appreciate any thoughts and suggestions.

 

[DirtDonk]

How about some detailed pics of the links and their mounting points? The geometry of 4-links is pretty specific on how it acts in different circumstances. And the "correct" geometry for certain things is not always easy to achieve with a factory chassis and body setup.
Maybe the PO fabbed it up expediently, but did not get all the link angles spot on for wheeling.

Anyway, that's just all talk on my part to subscribe and hear what others have to say about it. Plenty of members here are definitely link experts and might have some good insight.
Good luck. Must've been a very odd feeling!

Paul

 

[68ford]

What type of 3 link front? Can you move the sway bar end link closer to the actual bar and make it stiffer to try?

 

[BUCKWILD]

It will fell alot different and will unload some but like 68ford said try to shorten the arms a little or even see if you can get a bar diameter and look up its specks, my not be enough.

 

[Yeller]

Shock valving is huge as well getting coil overs tuned by a professional is time and money VERY well spent

 

[68ford]

Shock valving is huge as well getting coil overs tuned by a professional is time and money VERY well spent

While tuned by a pro is money very spent as you said, most of the time they are over valved out of the box and tuners lighten them up. While it will ride and perform better, I think in his case it won't make much difference or maybe even feel worse. Obviously I'm assuming they are on the stiff side now.

Need to know about the 3 link. If it still has radius arms, the front axle is probably a stiffer sway bar than the rear sway bar which would explain why it seems the rear moves more.

 

[broncomikem]

I’m out of town for the weekend, I’ll get some pictures when I get back. The front has y link type bars with a track bar. It seems to flex fairly well.

 

[Yeller]

While tuned by a pro is money very spent as you said, most of the time they are over valved out of the box and tuners lighten them up. While it will ride and perform better, I think in his case it won't make much difference or maybe even feel worse. Obviously I'm assuming they are on the stiff side now.

Need to know about the 3 link. If it still has radius arms, the front axle is probably a stiffer sway bar than the rear sway bar which would explain why it seems the rear moves more.

True to a point but if besides valving, spring rates nitrogen charge and oil level help control the package. I too am curious about suspension geometry, but the shocks and spring rates are also completely an unknown and can contribute to the issues described. Some additional pics of the suspension will be helpful as well.

Had a customer bring me a set of coil overs that we put on his buggy. It did all sorts of weird things, they were all low on oil. not saying that is the issue but everything has to work together. The more variables discussed the better the overall solution will be

 

[GWBronco]

I suspect geometry and or the sway bar. You said you have 16" CO's in the rear, but looking at one of the pictures above the rear tire is off the ground. I have 14's front and rear with the same suspension, except a true 3-link in the front not radius arms as what it sounds like you have, and my rear tire rarely comes of the ground. It appears either something is binding or the sway bar is to heavy or the shock length is not set up correctly. Where does the shock sit on level ground, how much shaft is showing on the shocks both front and rear?

 

[broncomikem]

I finally took some more photos.

 

[broncomikem]

I suspect geometry and or the sway bar. You said you have 16" CO's in the rear, but looking at one of the pictures above the rear tire is off the ground. I have 14's front and rear with the same suspension, except a true 3-link in the front not radius arms as what it sounds like you have, and my rear tire rarely comes of the ground. It appears either something is binding or the sway bar is to heavy or the shock length is not set up correctly. Where does the shock sit on level ground, how much shaft is showing on the shocks both front and rear?

I wonder if part of the rear tire coming off the ground has to do with the limit strap and the bump stops?

 

[68ford]

Willing to bet your front axle is working as a sway bar(radius arm suspension) and much stiffer than your rear sway bar. Path of least resistance, rear flexes easier than the front.

 

[68ford]

As above mentioned, rear side that goes up probably hits the bumpstop rear quick, then pushes the opposite side down.
If your not hiring bumps at speed and bottoming out regularly, I would suggest running lower pressure in the bumpstop. Perfect world, probably shorten them to 2in maybe even 1 in travel instead of 4in. Then you would have more up travel from ride height before hitting your bumpstops. Ride would probably be noticeably nicer

 

[broncomikem]

As above mentioned, rear side that goes up probably hits the bumpstop rear quick, then pushes the opposite side down.
If your not hiring bumps at speed and bottoming out regularly, I would suggest running lower pressure in the bumpstop. Perfect world, probably shorten them to 2in maybe even 1 in travel instead of 4in. Then you would have more up travel from ride height before hitting your bumpstops. Ride would probably be noticeably nicer

The bump stops are daystar, they have poly inserts, the travel is not adjustable, and if I was to give it more up travel the tires will rub. IAs it sets now, with anyone in the back seat the bump stops bottom out and makes for a rough ride, I would like to have more travel when driving.

 

[68ford]

I mean give it more up travel before the bump contact by shortening the amount of exposed shaft when they are extended. Fully compressed would be the same. Assuming they compress to where you can't see the shaft?

 

[68ford]

The bump stops are daystar, they have poly inserts, the travel is not adjustable, and if I was to give it more up travel the tires will rub. IAs it sets now, with anyone in the back seat the bump stops bottom out and makes for a rough ride, I would like to have more travel when driving.

Bye bye bumpstops, hello bypass shocks ;D

 

[Apogee]

Bypass shocks are amazing, but you could also ORI's and lose the coilovers, bumps and sway bars. A few guys on here are running the ORI's and making them work pretty well overall, noting that everything has pros and cons.

 

[68ford]

Bypass shocks are amazing, but you could also ORI's and lose the coilovers, bumps and sway bars. A few guys on here are running the ORI's and making them work pretty well overall, noting that everything has pros and cons.

I guess it depends on how he intends to use his bronco. I know at higher speeds, gas shocks have all sorts of issues with pressures rising and raising ride height and piston positioning. I think for all around use, retaining his coilover and sway bar and adding a bypass shock in place for the bumpstop, would give him the best ride and handling. Like KOH ultra 4 rigs, need to work going slow in rocks and high speed in the desert.
I'm sure when 4 people are in it and it rides on the bumpstops it's pretty bad. With bypass shocks, it would be in or close to the "bump zone" so it would be stiffer, but nothing like riding on the bumpstops.