SOA questions

So I finished boxing the frame, and I'm starting on the SOA. I'm using Wagoneer axles and 1 1/2 inch lift YJ springs. From what I've read, it seems that most people have to outboard the front spring hangers, but the rear ones can be left under the frame. When I went to position the spring perches on the rear axle, I found that the differential is in the way, even with RE's offset perches. Is this just the way it is and I need to outboard the rear spring hangers, or am I missing something here? I could grind a little bit off to get them into the right position, but I wouldn't really have room to weld it on next to the differential.

Also, does anyone know how many degrees I should rotate the spring perches before welding them on? I was thinking somewhere in the neigborhood of 6-8 degrees, but I want to be sure before I do it. Would this number be the same for both the front and rear axles?

Thanks.

 

Can't really help with the spring perch question since I'm not too familiar with Waggie axles but you might ask Tim (53Flattie). He put waggie axles SOA under his flattie.

As for the pinion angle, this depends if you plan on using a CV style rear driveshaft. If you do, then the pinion needs to point towards the rear output on the transfer case.

If you don't plan to use a CV driveshaft, then the angle of the pinion needs to match that of the rear output. Example: If the rear output points down 5 degrees from horizontal, then the rear pinion needs to point up 5 degrees from the horizontal. This makes the operating angle of the ujoints the same.

A more thorough explanation can be found here
http://www.pirate4x4.com/tech/billavista/PR-shaft/index2.html

 

That clears a lot of things up. I'm not really sure if I'm going to need a CV drive shaft or not at this point, so I think I'm going to tack weld the perches on in roughly the right angle for a normal driveshaft, and then pull the axles back out later on in the build to weld them up and possibly change the angles.

Does anyone know a ball-park figure on the angle of the rear output on the t-case? I'm not sure how to go about measuring that when I don't have the t-case or anything installed on the frame.

 

Your going to need to have your motor, trans, and tcase in there final spot and be as close to your finished weight on the springs before you can even thing about driveshaft and pinion angles. And you'll need a longer driveshaft anyway so your better off getting a CV shaft. What I did was grab a cv shaft from the front of a wagoneer and had a local welder cut it down for $40, then I pressed in some new ujoints and ran it. So for about $70 I had a custom driveshaft that would have cost about $350 to have made new. With a competent welder who knows what they are doing and if you keep the driveshaft yokes in phase you won't need to rebalance it.

You have an offset rear waggy 44 then? I would probably just hand fabricate a spring perch on the side of the diff. A little grinding and some welding, done... Way easier than out boarding the rear springs to!

 

Going back to this thread, when I did my SOA, using my stock axles with YJ springs, the right side spring perch was real close to the housing, but it's hard to say how it would be with the waggy axles.

As far as the driveshaft is concerned, I already made the mistake on mine of welding the perches in place before having everything mounted, so that full weight would be on the suspension. As a result my pinion is pointed up too much now. I am going to add a couple of leafs into the spring pack which will probably bring the u-joint angles pretty close to what they need to be. If I need to go more, then I will just install tapered shims. I am not running a CV shaft, and I am not having any problems with mine at all. I did however drill and tap (3/8 pipe tap) a new fill plug location further up on the housing to make sure I have enough fluid in the diff. With the pinion pointed up, if you use the filler in the cover, you will probably starve your pinion bearing for lubrication.

 

so far every ones got it right , pretty much what i would have said. as for the front axle, you dont really want to start playing around with changing the pinion angle on it. as you rotate the housing you will change your caster( or camber, cant remember which ) angle. this will result in some freaky steering to get around this you have to cut and rotate the nuckles and then reweld them.

i am in the proces of doing front and rear 44's in my jeep as well. i am using a scout 44 in the rear and a waggy 44 in the front, which i have to go out-board with the springs as well. also doing rear disk brakes, with all parts from the auto wreaker, only cost me $40 so far

 

When I put the Waggy axles under the flattie - I didn't have any interferance with the rear perches and the diff - FWIW.

On the front, just as was mentioned, altering the pinion angle with alter the caster. I had to rotate the pinion upwards and used a CV shaft to keep from binding. As a result, I had to have the knuckles cut and rotated to return the positive caster.

Let us know if you have any more questions.

 

hey dan i will start a post in the fab section, and then i will follow it along as i do it i will say it uses all exsisting front end parts, which i got from the wreckers. it will still be a semi-float as the way that my buds and i are doing the full-float set up isnt quite working yet. well.... it works fine except that for the shafts we have been cutting the splines on the one end and that hasent been working out so well....... keep breaking them

so my bud is looking at getting some tooling to be able to roll the splines, once that is in place then i wll probably switch to that set up.