Rear Coilover, Long Travel, Custom Linkage Thread

[1985taylor1925]

I searched for a thread like this using the advanced search, and didn't find anything comprehensive. So I would like to compile this info into one thread.


I'm interested in seeing what you guys have done to customize the rear to accommodate long travel, coilovers, etc. In the future when money comes available I would like to go with a King rear coilover setup. My plan is to go with

- king dual spring rate coilover with 10" or 12" travel on the shock
- extended rear lower control arms
- watts linkage

Im not sure if these are the best prices, but these guys offer any rear King of Fox configuration you need. Off Road Coilovers - Off Road Coilover Shocks | Off Road Shocks


I've spent a good deal of time looking at the rear linkage, measuring and trying to figure out what would work. One of my goals is to eliminate the panhard bar. 4 link would be a good option to do so. But I've been obsessed with watts link since I first leaned about it a few years ago.

Anyways, we have a good number of engineers and a lot of amazing fabricators on this forum, so I wanted to see what you all have done to customize the rear to make long travel/coilovers/custom linkage work. Rock crawlers and Baja runners, please chime in!

 

[JayRolla]

These guys make cool stuff.

Toyota 4 Link Kit

 

[1985taylor1925]

These guys make cool stuff.

Toyota 4 Link Kit

Nice. Ive never seen this site. Their brackets look bomb proof! That does make 4 link very appealing. Its such an efficient design. I have a fair amount of fabrication experience, though it's from working on F-16s in the ANG, not vehicles. But my brother is a fantastic welder and fabricator. So I think I would borrow ideas from different designs and then work with my bro on the fabrication.

The thing about watts link, it has to be designed right to provide good clearance and travel, but in looking at the rear end it would actually be really simple to apply to our trucks. And would be fantastic for on road handling.

 

[4Running Daily]

Watts linkage is a good design. A traditional 4-link is a good idea too.

However, in order to accommodate our gas tank, the best way to go is 3-link.
This is the route I plan on going:
Basically you have one upper link, two lower links the coilovers mount off of, and a pan hard. This will allow you to pull 20+ inches of rear travel using a 14" or 16" coilover.
20150831_103242 by Connor Rhoades, on Flickr
20150831_103309 by Connor Rhoades, on Flickr
BEB4C39A-9842-4EEC-A20A-FF08ECC396E9 by Connor Rhoades, on Flickr
D9C5EF28-D6A3-4065-99D9-4D5AB6EC92A9_1 by Connor Rhoades, on Flickr
Link to it in action: https://www.youtube.com/watch?v=RsdLs-dPaGQ

If you aren't opposed to moving the gas tank and doing a f150 swap. Then you could run a wishbone setup, which is similar to a 4 link. A fellow member did it. However, with this option, you're limited to 1:1 ratio of coilover travel to suspension travel, because the coilover is mounted to the axle. So expect 15" of travel with a 16" coilover.

Screen Shot 2014-10-06 at 1.06.56 PM by Connor Rhoades, on Flickr
IMG_2723 by Connor Rhoades, on Flickr
IMG_2731 by Connor Rhoades, on Flickr
IMG_2760 by Connor Rhoades, on Flickr
IMG_2754 by Connor Rhoades, on Flickr
IMG_2764 by Connor Rhoades, on Flickr
IMG_2774 by Connor Rhoades, on Flickr
IMG_2787 by Connor Rhoades, on Flickr
IMG_2788 by Connor Rhoades, on Flickr
IMG_2789 by Connor Rhoades, on Flickr
IMG_2580 by Connor Rhoades, on Flickr
d by Connor Rhoades, on Flickr
Screen Shot 2014-10-06 at 1.07.16 PM by Connor Rhoades, on Flickr
[MENTION=92884]snivilous[/MENTION]

 

[1985taylor1925]

Watts linkage is a good design. A traditional 4-link is a good idea too.

However, in order to accommodate our gas tank, the best way to go is 3-link.
This is the route I plan on going:
Basically you have one upper link, two lower links the coilovers mount off of, and a pan hard. This will allow you to pull 20+ inches of rear travel using a 14" or 16" coilover.

20150831_103309 by Connor Rhoades, on Flickr
[/MENTION]

Hmm. The gas tank was one of the first things I noticed when looking at ways to do custom upper arms. I never thought of doing an offset 3 link like that. That would certainly work. I'm not going to be jumping my truck, so I wouldn't need to go as far as the fox setup. But that is some fantastic geometry.

I think for me something like the above would work well, but I would still go with watts link. I can see that the panhard bar in the picture is longer than stock which helps reduce the severity of the arc. That would help some with road manners. But man, watts would be cool. Wouldn't need the lower arms to be that long. Looking at the lower arm brackets on the frame, I think I would extend them forward maybe 6" to 8", and of course make them adjustable.

For the issue with travel, I would angle the coilovers in toward the top, mounted inside the frame to get more travel. Basically close to the angle the shock currently mounts, but angled a little more, and would to cut out the original shock mount to get them higher up there. That way I could hopefully get away with a 12" travel coilover. One possibility is to move the coilovers behind the axle. Much more room to work with. And then they could be angled inward and slightly backward at the top.

Whose truck is that with the custom fox longtravel?

 

[snivilous]

The way I've wanted to go, but ultimately time and money over the summer stopped me, is a 4-link and cantilevered coilovers similar to what [MENTION=84548]NoHair[/MENTION] does on his 2nd gen as I recall.

Tons of different ways to do everything, all depends what you want. Personally I want a lot of travel, fully redundant links, no panhard pulling the axle around, and everything tucked under the truck so I don't have to go into the body. And considering I have 14" of travel up front I want more than that, I can only fit a 14" travel shock above the axle in the wheel wells, and would have to cut the body for trailing arm mounted shocks, so a cantilever moves everything out of the way and can get a big motion ratio to amplify the shock travel to what I want.

 

[RockenAlex]

I have in no way thought this through to the point of measuring and designing it. But my plan goes as follows:

Drivers side, remove stock fuel tank. Passenger side, remove exhaust and reroute, remove flooring mirroring gas tank (where stock jack and tools reside) and weld closed, cut gas tank crossmember out (i don't believe this is connected to the tranny but i could be wrong). This should allow for the entire area underneath the rear seats to become vacant or anything besides the driveshaft.

Traditional 4 link to the axle. Devise a shock mounting jig inside the newly vacated space below the passenger seats. Then mastermind a cantilever setup to allow the shocks to be mounted parallel to the ground within this space. The C/O's will likely be no more than 12" for cost and space reasons, but with a cantilever by adjusting the geometry you can achieve different ratios or axle to shock travel. My goal of axle travel will be based on whatever I devise for the front as well.

The real goal of the design will also be to keep everything as compact and protected as possible. I would like to simply have the link attached to the axle. Everything else from shocks to bumps will be based off the cantilever setup.

The most straight forward inspiration i have found is the Jeep JK EVO lever. My design will resemble this in many ways but be reversed to sit in front of the axle rather than to the rear.

 

[PhdNPrerunners]

Here is a 3rd gen that Camburg did a long time ago and they did a 3 link similar to what 4running Daily was talking about. These are the only pictures I have of it.

 

[zak3033]

I'm glad you started this thread. I am slowly building up my 2wd 4Runner and I'm eventually going to make a coilover setup in place of the existing springs. I'm aiming for a decent mid-travel setup but if I get the chance to do it I will post pictures.

 

[Turbonate]

This is what I did. Pulls about 12" handles really well in the desert

 

[HiluxSurf SSR-G]

May I know what vehicles use the watts linkage? is that a reliable system?

Thanks.

 

[snivilous]

May I know what vehicles use the watts linkage? is that a reliable system?

Thanks.

Since we are talking custom LT, I'm sure most people in this thread have seen the Dual Sport guys setup with a Watt's Linkage: Dual Sport 4runner - Page 3 - TTORA Forum

In reference to you HiluxSurf, I don't know of any stock platforms that use a watts linkage and from my research it's primarily used for track cars--but don't mistake that for meaning it's not suitable for offroad use.

My $.02 on Watt's Linkage--it's sexy, but that's also the issue with it. Lots of moving parts going on, more parts inherently means less reliability, etc. Everyone has their preferences, imo I like a triangulated 4-link because it is COMPLETELY redundant, so if any of the mounting points breaks or becomes unattached you could still drive. Nothing inherently wrong with a Watt's setup as far as I can tell though.

 

[A.Wilson013]

Would a 3 link be acceptable to daily drive? Seems like it'd less than ideal for road manners.

 

[4Running Daily]

Would a 3 link be acceptable to daily drive? Seems like it'd less than ideal for road manners.

Oh it would be fine. You could even run a sway bar with it too. One of the currie sway bars

 

[snivilous]

I've started kicking around ideas again for what to do over the summer when I'm not in school and have access to a shop back home. I wanted to do a cantilever setup, but I'm not sure how feasible and realistic it is to do everything needed for it in 3 months while working full time and then needing everything good to go to drive back to school.

I've seen a few guys running coilovers in the rear and mounting them in the wheel wells (usually SAS guys). One of my main goals over the summer is to get a wider rear axle, so I don't think I would have rubbing issues once the rear is widened 6-9". I measured a few months ago and I think I can stuff a 14" shock in the wheel wells without cutting into the body at all, based on where my bump stops are right now which is on the lower end of what I was thinking but would be a lot better than I have now and at least matches the front end.

Any thoughts before I put more brain power into this? Simple triangulated 4 link, ~14" coilovers, hydro bumps, widened rear end. I think that would do pretty well if I get some resi kings, maybe see if I could fit a secondary shock in the future.

 

[4Running Daily]

I've started kicking around ideas again for what to do over the summer when I'm not in school and have access to a shop back home. I wanted to do a cantilever setup, but I'm not sure how feasible and realistic it is to do everything needed for it in 3 months while working full time and then needing everything good to go to drive back to school.

I've seen a few guys running coilovers in the rear and mounting them in the wheel wells (usually SAS guys). One of my main goals over the summer is to get a wider rear axle, so I don't think I would have rubbing issues once the rear is widened 6-9". I measured a few months ago and I think I can stuff a 14" shock in the wheel wells without cutting into the body at all, based on where my bump stops are right now which is on the lower end of what I was thinking but would be a lot better than I have now and at least matches the front end.

Any thoughts before I put more brain power into this? Simple triangulated 4 link, ~14" coilovers, hydro bumps, widened rear end. I think that would do pretty well if I get some resi kings, maybe see if I could fit a secondary shock in the future.

Where are you moving the gas tank? Seems nice and easy, but even wider you have to think about where your tire is going to tuck. Especially articulating.

 

[snivilous]

Where are you moving the gas tank? Seems nice and easy, but even wider you have to think about where your tire is going to tuck. Especially articulating.

Just to the spare tire location probably, assuming I can't figure out how to go around it.

And I agree on the articulation, right now I still rub if I flex enough so I'm already planning on trimming the rear wheel wells as much as possible. Otherwise I'll just have to drop the bumps lower, maybe jack up the rear a little to get some up travel back.

 

[JWaldz]

I'll be looking at 4-link in the future. I'll likely just notch the frame and reinforce it really well. Maybe mount coilovers off the lower links. I wont be going off jumps and woops, just slow crawling, so it shouldn't be an issue. I haven't really decided anything else beyond that. It'll be as simple and effective as possible. Likely wont go over 18" coilovers, depending where I put them. The diamond I got is 63", which I believe is 2.5" over stock width. If I have to run rear spacers then so be it, but think I'll be ok.

 

[rossgoldie]

This is what I did. Pulls about 12" handles really well in the desert

What coils are you running?

 

[orbot]

What coils are you running?

thats the set up im my future. i plan on the OME 890 coils because i dont want that big of a lift and i dont carry much crap