[punkur67]

Here is my ford 9" that I just rebuilt for the fairlane. Goodies include:
-All new bearings
-Full Spool
-custom disk brakes that I made brackets for
-Mosier 31 spline axles
-Re-used 4.11 gears
-braided brake lines
-fill and drain plugs with billet fill cap
-Housing truss

Worknig on my home made cal-trac bars now.

 

[punkur67]

I have about $85 in the rotors and calipers and another $60 in lines (these could be cheaper if not braided). WAY cheaper than kits sold by people online, especially the bolt on ones. You can get weld on setups for around $300 and bolt on around $400. Most of the kits don't include the complete lines and use the small calipers. I am going to run them for a while, and if they work good will consider selling the brackets.

 

[dennis112]

Very nicely done! :tup:

One question though--why didn't you box in the spring perches?

 

[punkur67]

I did not think to do that. Honestly I did not know about people doing this, but its a great idea.

 

[dennis112]

Fair enough.

It is almost mandatory with a performance leaf spring car to box the perches. The rear you built says performance all over it. The perches shown on your rear are considered light duty and they will bend under extreme acceleration, especially with sticky tires.

Its pretty easy to box the perches. You can use small pieces of 3/16" or so metal to box the front and rear of the perch to the rear end tubing, or you can bend a strap and run it all the way around. You can even get aftermarket heavy duty ones that included the additional support. Just be cautious of not applying too much heat to the whole housing at one time as it might tweak. Here are both types shown on 1 photo:

Boxed on the left, strapped on the right. The strapped one was removed when the rear was narrowed.

 

[punkur67]

I might need to move the perches anyways. I put the rear end in today and the perches would not line up with the springs. The perches are located about 1-1/2" narrower than the springs. I can install new perches or build offset rear shackles. I did not notice when I took it all apart. But with the aluminium front any poly rear bushings, it was very noticeable. It looks to be the stock rear end. Maybe swaped from another car before I got the car.

 

[dennis112]

The springs do not always bolt in at the correct angle under the car and that may be what you are seeing. If that isn't the problem, then I am not sure if the offset rear shackles will be the correct fix for the situation. You might create a different binding situation.

Properly spaced leaf springs will toe in a little toward each other in the front, or at least be parallel. Less than an inch will be correct with 1/2" preferred. They should be drawn in tighter in the middle where they meet the perch. I wouldn't want to get too far away from this or else it could affect the handling of the rear suspension. That said, after the minitub I ended up with mine being 1/2" wider at the front vs. the rear and it didn't seem to make any difference (at the track.) I see no reason to change it now.

New HD spring perches are in the $40 range and will include the additional support front and rear. My 9" has 3" tubes, yours appear to be tapered so could be smaller.

 

[dennis112]

N/M

 

[PSIG]

Nice. What are you using for parking brake? If your tubes are 3" at the mount, Speedway had pads for $12.99 a pair here. You can reinforce with light sheet metal to box it, as the stress is all in lateral tension. The failure mode under torque is for the pad channel sides to flex outward, so you just need something to keep them from spreading, like a 1/16" plate over the 'opening' on the rear side of the axle. The front will not have compression stress, and does not need to be reinforced, but I do just to complete the closed design and eliminate a crap trap area.
:tup:
David

 

[punkur67]

No parking brakes. They were completely removed when I got the car. The only thing left was the pedal. I'm ok without one though. I just make shure to park on flat ground. I have the small bearing housing, I think they are 2-1/2" tubes.

 

[punkur67]

The springs do not always bolt in at the correct angle under the car and that may be what you are seeing. If that isn't the problem, then I am not sure if the offset rear shackles will be the correct fix for the situation. You might create a different binding situation.

Properly spaced leaf springs will toe in a little toward each other in the front, or at least be parallel. Less than an inch will be correct with 1/2" preferred. They should be drawn in tighter in the middle where they meet the perch. I wouldn't want to get too far away from this or else it could affect the handling of the rear suspension. That said, after the minitub I ended up with mine being 1/2" wider at the front vs. the rear and it didn't seem to make any difference (at the track.) I see no reason to change it now.

The rear shackles are much narrower than the front spring mounts. They are pulled so hard, the front traction bar plate won't move cause it is pinched between the spring and mount. I will measure the front mounts, spring pads, and rear mounts. Seems if I just moved the rear mount with an offset shackle that would take the tension off them at the spring.

 

[punkur67]

Just measured everything. The front and rear spring mounts are 45" center to center. The spring perches are 43" center to center. Seem like new perches are the fix. Should I be worried about welding the with everything assembled, or should I tear it all apart?
all that time painting it all nice for nothing.

 

[dennis112]

Just measured everything. The front and rear spring mounts are 45" center to center. The spring perches are 43" center to center. Seem like new perches are the fix. Should I be worried about welding the with everything assembled, or should I tear it all apart?
all that time painting it all nice for nothing.

Yep, moving the spring perches to equal the distance is the answer. Welding them on is no big deal, just don't get the housing length real hot. I first tack the perch to the housing and let it cool while using wet rags on either side of the area to be welded to prevent warpage. Then I finish weld, allowing a little time between runs. The bracing that you've done should help too.

Also be aware that you will want to duplicate the existing perch location in relationship to the pinion. Support the housing upside down and level the old perches. Remove and replace 1 at a time, ensuring level when done.

If you wanted to change your existing pinion angle, this would be the time to do it-assuming it was measured before. Otherwise, make the perches level and use shims once the angle has been determined.

 

[punkur67]

I just picked up some heavy duty spring perches from a local off road shop. They are stamped out of at least 1/4" thick steel. Gunna pull the rear out tomorow and cut the perches off.

 

[punkur67]

Got the perches on and boxed the new ones as recomended.