More SOA Q's before I start my build over christmas break

ntsqd · 04-17-09, 08:55 PM

I've not had any issues with the built-up hoses, but then the accumulated miles on them has yet to be very significant. That is about to change as both my Mini and my 6T will shortly be sporting them in all locations. The Mini has had the rear already in place for maybe 25k miles. What prompted the idea of carrying the bits to allow a field repair/replace was a trip with LocosMocos to pit the Baja 1000 in 2001.

I guess I'd better look into the diff guard thing.

Cruiserdrew · 04-17-09, 09:33 PM

Chicago-I'll take the other half of that diff hat if it isn't spoken for.....Let me know $$ and happy to share costs and your plasma cutter.

Butt Ugly Chuck · 04-18-09, 02:14 AM

Quote:

Originally Posted by Randy88FJ62

What have people done about extending their sway bar mounts? Is there a kit available or is it mostly custom since all SOA are different? I don’t want to ditch my sway bars as I like to drive my rig around and also I drive long distances to the trails.

Been a while since I checked this thread....

Check with orangefj45. He was working on custom kits a while back.

Butt

Randy88FJ62 · 04-18-09, 06:39 AM

Quote:

Originally Posted by Butt Ugly Chuck

Been a while since I checked this thread....

Check with orangefj45. He was working on custom kits a while back.

Butt

Good idea. If he has a brake line kit then I would go for it. It's kind of small potatoes though, not sure he would be into that stuff unless he was doing the SOA at his shop.
-Randy

UPDATE:
Sitting at LAX waiting to go to Japan for 1 week business trip (and see Mot

.)

Randy88FJ62 · 04-20-09, 02:53 AM

Question about front shocks: How do I know where to weld the front ford upper shock mounts? What do I need to consider to maximize articulation, droop, and ride? I plan on using Marlin Crawler's axle gussets which include the lower shock mounts.

GLTHFJ60 · 04-20-09, 07:23 AM

Question on the brake line issue. Noticed yesterday when pulling apart the rear axle on an 80 that the rear caliper uses a banjo bolt and ~6" long soft line to the hard line on the rear axle. Could this bolt and soft line be used on 60's front calipers?

ntsqd · 04-20-09, 10:36 AM

A banjo fitting requires a machined flat spot around the fluid port for the crush washer to seal on. I do not recall either the FJ or the 4rnnr caliper having this feature. Could put it in with a file, but filings issues aside, it also needs to be perpendicular to the hole within a fairly close tolerance. It could be done by someone sufficiently talented, but I wouldn't recommend it. A straight adapter with a 90* hose end is pretty tight to the caliper body.

The way that I was taught to set the upper shock mounts is so that with the axle fully bottomed out , 1/2 way compressing the bump-stop) on that side, and the other side hanging in space that the damper is still ~1/4 shy of being bottomed itself.

Randy88FJ62 · 04-21-09, 05:26 AM

ntsqd,
Could you explain that a little more? I'm understanding from your statement that I need to cycle the suspension in order to measure the mount placement. Just wanting more details.

If anyone else could also explain why they chose their angles and palcement I would appreciate it.

To keep in mind, I will be going for a low SOA with stock shackles and stock FJ60 springs.

ntsqd · 04-21-09, 08:57 AM

Presumably you've chosen shocks with enough travel that they are not going to limit your travel. Hitting the limit of the shock's travel before the rest of the system limits out is usually a bad thing. The worst case is at full compression. Rarely does full extension happen at high velocity, but full compression nearly always happens at high velocity.
High velocity full extension is pretty hard to do since you only have spring rate and axle mass working for it. Usually those speeds are low enough that the shock can handle it without damage.
High velocity full compression is much easier to do since you have vehicle speed and mass working for it. Rarely are those speeds slow enough that the shock can handle it without damage.

So setting up the mounts to keep the shock from full compression when the suspension is fully compressed is my first priority. This would be easy if the bump-stops were part of the shock and I didn't need to worry about articulation. The further away that the bumps are from the shock, the more that articulation affects where the upper mount needs to be to keep the shock from becoming the new 'bump-stop'.

I don't really cycle the suspension for the lower mount. I do take the cycling into account when deciding where to put the lower mount since that drives where the upper will likely be. I find it simpler to fix the lower in place and then go to fully articulated compression to find the upper location, rather than trying to worry about where things will also be at full extension. If the length of the shock is right then full extension is not important.

If this were some sort of off road racer I would first remove the bump-stops and then set up the upper mount based on metal to metal contact. The reason is that off road racing is hard on bump-stops and you can not count on them always being there. Once they're blasted off the vehicle I still want the shock to come home in one piece.

Randy88FJ62 · 04-21-09, 02:56 PM

I have not chosen shocks yet as I was going to first see how much compression the suspension could get. My bottom front shock mount will already be in place due to using marlin crawler's knuckle gusset shock mounts.

I guess my real question is what angles work best for shocks? I have never done this or seen it explained. Should the shocks be vertical or have certain angles?

ntsqd · 04-21-09, 03:06 PM

If you want to be anal and picky about this then you want the most shock piston speed (Motion Ratio = High) at the compressive limit of the travel. The idea is rising damper rate to do the best job of slowing down the axle before hitting the bumps.

Within the constraints of the available mounting options it's something to shoot for, but don't be surprised about falling a little short. Doubt that it will make much difference anyway.

ChaseK · 07-07-09, 09:48 PM

So whats going on with the build now man? Been reading your whole thread trying to get an idea of what to do with mine...

Randy88FJ62 · 07-08-09, 08:50 AM

Front axle housing should be back within a week or two then it's getting rebuilt and going back under the truck.

Randy88FJ62 · 07-08-09, 08:59 AM

Quote:

Originally Posted by ntsqd

If you want to be anal and picky about this then you want the most shock piston speed (Motion Ratio = High) at the compressive limit of the travel. The idea is rising damper rate to do the best job of slowing down the axle before hitting the bumps.

Within the constraints of the available mounting options it's something to shoot for, but don't be surprised about falling a little short. Doubt that it will make much difference anyway.

I started googling some of the phrases you described above about shock piston speed and I ended up in the expedition portal forum reading one of your other posts ntsqd