Anxious to work on the Runner. Been rolling a few ideas around in my head with what to do in the rear. I want to pull 20" of travel at least (full droop, not flex). No reason in specific except I know that's attainable and I want to get into the 20s with rear travel, especially if I can modify the front to pull over 14". I also don't want to go into the body, and I want it to be fairly simple.
Because I want "so much" travel in the rear, I obviously need to run some kind of suspension to give me a multiplier since the largest shocks you can get are 18" coilovers--which I'm also gonna stay with a linked rear, I hate the idea of leaf springs and their lack of adjustability. I also don't want to run the stock geometry for various reasons, the main being that it binds up way too easily (as proven by breaking both my upper links with an essentially stock setup).
I could run trailing arms (eg. run my shocks to my trailing arm and essentially create a cantilever to multiply my travel at the axle), but stuffing a shock I would certainly have to go into the body. I also thought about running a cantilevered trailing arm setup, but thinking about it I think that's not necessary and the only reason to do it would be to have two travel multipliers (the cantilever, then the trailing arm). So that has led me to think a basic cantilever is the best idea, that coupled PROBABLY with a normal triangulated 4-link.
I'm not too worried about fitting the 4-link, if the gas tank has to move then whatever but I don't really think it'll have to. I was thinking about running the upper links to the lowers, no idea what that's "technically" called but then I could just run my link brackets off the frame. Downside with that is I don't have redundancy (where as a full 4-link is completely redundant) and I don't like that, also I don't think it would flex very good but I'm not sure... I need to draw it up in CAD to figure that out. I was also thinking I could run the upper mounts to a structure around the gas tank, essentially have some massive skid plates on the underside that double as my link mounts but that wouldn't be fun to do maintenance with. Anyways, I'm not overly concerned with the link setup--one thing I just thought of (which is why I'm writing all of this down

) is I could run a normal 4-link super far out on the axle, run both links on each side to the frame and then run two secondary links that go from the middle of the axle to like halfway up the lower links. That way the lowers take the lateral load of the axle, while nothing gets in the way of the gas tank or anything and everything remains redundant...
Moving on, after reading a bit and looking at pictures:
canitlever shock mounting, theory and design - Pirate4x4.Com : 4x4 and Off-Road Forum It seems a cantilever will probably be pretty easy to fit where the spare tire goes. I'm thinking of doing two shocks side by side, a bypass and a coilover, and then have like heims or bushings or some kind of bearing attaching to the pivot point of the cantilever stucture since there won't just be a straight load path since obviously two shocks are valved differently and then one is spring loaded, so a wide base with some beefy sexy mounts instead of just a bolt running through the pivot. And I want a sway bar, after riding around in Cartzo's 4Runner the body roll is insane but it's so smooth and obviously I won't be able to run the stock setup. It would be cool if I could run something connecting the two cantilever structures and use that as a sway bar, I mean there's not really any point having two sets of links per side going to the axle... I don't know how I would disconnect it though, that might take some thinking (or maybe just have a sleeve that connects two steel rods coming out from the cantilever pivot and have the sleeve pinned to transfer torque). Then I'll probably just run the bump stops on the outside of the frame.
Anyways, nothing exciting but I wanted to write everything down and compile my thoughts. I'm not too worried about fabricating all of this, the links are super straight forward and I'll use 4-link calculator and then model it in solidworks and do long hand analysis to double check everything and the cantilever setup I'm not worried about either which is the most complicated part. All in all I think it'll be a lot easier than the double A-arms I designed, not to mention I'll have my dads shop. Now I just need to get home and get cracking...
EDIT: The 4-link with two extra links is kinda retarded, I could just run the lowers angled. So it'd be like an inverted triangulated 4-link. I don't see any reason why that wouldn't work!