Since this thread got re-filed, I'll update some of my research:
Called a pick'n pull in Nebraska 8hrs from my house. They've got an FJ80 front for $800. It's the full floater with the electric locker. Comes with everything that's normally attached to the axle (coils, radius arms, steering stuff).
I really can't see doing leafs. I know they can be designed to work just as well as many coil/link suspensions, but I'm committed to climbing up the technology tree on this project. With a link setup you control axle wrap, have better departure/approach angles, better ride quality, and road manners, with all the flex and traction that I'll need. Here's a great intro to 4-links:
http://4wheeloffroad.com/techarticles/suspension/131_0307_link/A great book on the subject is Race Car Vehicle Dynamics by Milliken and Milliken. I'm a mechanical engineering student, so this sort of thing is a lot of fun.
Pre-IFS hubs are required to convert the 80 from its stock drive flanges. I'd use the fj brakes, and change to the larger cruiser master cylindar to help with stopping all the extra weight of big tires.
The thing that's really got me stumped is the steering. Stock, the arms attatch to the bottom of the knuckle, which sucks. Just from looking at pictures, there are two holes on top of the knuckle (bearing cap?), but It doesn't seem like two bolts would be enough for a beefy suspension buildup. Without getting my hands on an axle, I'm betting there's not enough material there to machine a few more holes for custom steering arms. Fireball had mentioned full hydraulic steering, but he did a custom setup using the top bolts, so I'll check into those options.
The reason I originally considered the fj80 front axle swap was:
-the mini axle is narrower than my ifs rear. As I lift the truck up, I also want to go wider to keep it stable.
-the mini axle has problems with birfs. There's two ways to fix a weak part: make it bigger, or make it out of better material. With the 80, I can do both
-the mini axle is low pinion. T'ain't nuthin wrong with that, but I'd like the high pinion for clearance and drive shaft angles.
-the mini is open diff'd. The 80 can be purchased with the toyota e-locker. The truck will continue to serve mild DD duties, so it needs to be road friendly (selectable locker is mandatory)
- By the time I put chromo longs, a high pinion diff, a selctable locker, wheel spacers, fj brakes and a new truss on a mini axle, I'd have spent plenty more than the 80 would cost.
-I considered other full width options D44, D60, but I think the 80 is comparable for what I want, and I like the idea of keeping things Toyota.
As I go, I'll keep this updated with what I find. I think the 80 swap could be the SAS meat and potatoes for the future.
