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Discussion Starter #1
This will be the first time I touched the rearend in this car. I need to fit the
15x8's or 15x10's (Corvette Rallys) and set it a lil low. What should the flange
to flange measurement be at fit-up? Am I looking at full pen butt weld or a
combination of plug/fillet welds?I also need as much info as I can get on
re-splining the 31 spline axles and re-drill(?) for the rallys(?). Can I effectively
keep the monoleafs? Drum set-up is my intention at this point.
 

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I believe Moser can cut and respline the axles and redrill them. Although it's probably not much more to just get new alloy ones made up.

A good but weld is usually good enough. If you want to make it better you can sleeve it or add some gussetts.
 

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Discussion Starter #4
Hey Tom

:confused::confused::confused:
Take it to a shop that has the alignment jig to do it properly.
Tom
What does this JIG look like? Is it just a fixture employing a rod & vise?
MIG welding is a little cooler process than the others. The original fillet
holding the flanges isn't even flushed out. Stabbing in new flanges,
keeping everything plum thats all there is to it? Right?
 

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You need bushings installed into the bearing housings in the housing ends and also in the center carrier and the rod passes through to keep the components aligned. As you weld the ends on you can twist the rod by hand to see if things are staying aligned- every weld pulls as it cools and keeping it aligned is very hard to do. The better shops that do this will have a fixture that rotates the complete housing during the welding process so they get a complete weld all the way around the housing in one pass- this cools evenly and keeps the distortion to a minimum. Bottom line is if you can't turn the rod the housing is misaligned and you'll need to figure out where the misalignment is and use a press the straighten it out. I narrowed one housing and don't know if I'll ever do it again-we fought witl alignment through the whole welding process and when we installed the back brace it really got interesting!

There's a lot of people that say this is easy- and there are a lot of pro street cars out there with misaligned rear wheels-check them out at the shows and race tracks tire wear doesn't lie. Spider gear and bearing problems are also common with poor narrowing results. Even welding spring perches on can warp the rearend tubes.
 

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Discussion Starter #6
Thanks Baddbob

How much clearance do I need between the monoleaf and the brake assembly
backing plate? If in the future I wanted to convert to disk,would I need more
clearance and be stuck with having to keep drums? Pictures to come
 

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You need bushings installed into the bearing housings in the housing ends and also in the center carrier and the rod passes through to keep the components aligned. As you weld the ends on you can twist the rod by hand to see if things are staying aligned- every weld pulls as it cools and keeping it aligned is very hard to do. The better shops that do this will have a fixture that rotates the complete housing during the welding process so they get a complete weld all the way around the housing in one pass- this cools evenly and keeps the distortion to a minimum. Bottom line is if you can't turn the rod the housing is misaligned and you'll need to figure out where the misalignment is and use a press the straighten it out. I narrowed one housing and don't know if I'll ever do it again-we fought witl alignment through the whole welding process and when we installed the back brace it really got interesting!

There's a lot of people that say this is easy- and there are a lot of pro street cars out there with misaligned rear wheels-check them out at the shows and race tracks tire wear doesn't lie. Spider gear and bearing problems are also common with poor narrowing results. Even welding spring perches on can warp the rearend tubes.
X2!!!
Most people warp the rearend and don't even know it.
I don't know how many I have seen that were way outta whack because of back braces being put on or incorrect narrowing processes
 

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if i where you i would pm techguy and talk to him about there (www.cachassisworks.com) rearend narrowing jig and axle housing ends for your 9'' i have a moser built 9'' in my 63 its the stock lenght as the 10 bolt the housing ends for my 9" are the big ford type but have gm brake backing plate bolt pattern check out what i mean at www.moserengineering.com
 

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I narrowed one housing and don't know if I'll ever do it again-we fought witl alignment through the whole welding process and when we installed the back brace it really got interesting!
Im curious what tube ends you welded or did you try to reweld the stock tube ends back on.

Another thing to think of is that some stock tubes are barely welded on. What do you think happens when you put torque through the axle. Those ends are never going to be perfect even if perfectly welded. I believe the rear differential has enough play to compensate. I would think a good jig, taking your time with the welds, assuring your cuts and grinds are accurate when measured should give you a very good quality end.
 

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There are alot of things I will tackle. Ill bend and flare my own brake lines. Do all the fuel and electrical. Assemble an engine with tight tolerances. Dabble with some body work.

But there are a few things that intimidate me. A full blown transmission re-build is one. Dont know enough about them. One other would be a rear end housing. Say to shorten one and line up the wheel bearing ends.

I just dont have the jig to do it. And I could make one, I think. But the work to make a proper jig will cost me in time and materials, mostly materials cause I have the time. As far as I know, it needs to perfectly lined up. And I can weld, no prob there. But because I have welded up some items I know how much metal wants to move. To do it right IMO you need a SOLID fixture and the cost of the materials is gonna be a waste for me for a one time effort.

So my fixture would be more than a solid bar though the center of the tubes. It would hold the center section firmly while supporting the ends also, before the center bar is in place. The bar in the center is just for alignment purposes, not structural support during welding. So a proper jig would need to be heavy enough to hold the center and its tubes and the flanges, all very stout. Then use the center bar for alignment purposes only, not supportive.

Thats just my take on it. Im sure you can use a center bar and align it up and weld and it will come out scrub free. I cant, or wouldn't. Different machining practices I guess. I see them as tools. One is for alignment and the other for keeping the alignment. Work holding and work positioning. JR
 

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Im curious what tube ends you welded or did you try to reweld the stock tube ends back on.

Another thing to think of is that some stock tubes are barely welded on. What do you think happens when you put torque through the axle. Those ends are never going to be perfect even if perfectly welded. I believe the rear differential has enough play to compensate. I would think a good jig, taking your time with the welds, assuring your cuts and grinds are accurate when measured should give you a very good quality end.
I reused stock Ford bearing ends, had them chucked in a lathe and cleaned the factory weld off to save the flange and they fit perfectly into the rearend tubes. Keeping it straight during the welding process was the difficult part. I've done my own driveshafts in the past and also other difficult welding tasks but this housing work was a major challenge to keep alignment on. A dedicated fixture made of stout material to control alignment during weld shrinkage would be the ticket and also doing the weld in one continuous bead would help to equalize the shrinkage.

If I can do it you can do it, but be prepared once you throw the weld down things move around real fast. Don't settle for good enough- the alignment rod needs to pass through all the bushings and you should be able to turn it by hand if there's no binding and alignment is good. Assemble the rearend and mount some wheels on then take a toe measurement between the wheels top, front, bottom, rear and all should be within 1/32" or better if your wheels are true.

I plan on doing a Dana 60 soon to try my skills again but not looking forward to it.
 

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How much clearance do I need between the monoleaf and the brake assembly
backing plate? If in the future I wanted to convert to disk,would I need more
clearance and be stuck with having to keep drums? Pictures to come
I think most of the disk brake kits position the caliper far enough upwards to not be a problem with clearance on the spring perch. The Ford explorer package I know doesn't require much room, but if I remember right there may be problems with shock clearance as we had to move ours inboard of the spring.
 

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This place seems to sell the lineup blocks.

http://www.mittlerbros.com/rear_end_parts__accessories.htm

They actually have the instructions in a downloadable pdf.

http://www.mittlerbros.com/PDF_Files/1000-RENK1 Instructions.pdf

Edit:

I just read through the narrowing instructions and it mentions to have all brackets welded before hand. Makes sense to set the jig and weld the ends after all this to get an accurate result. I wonder if this is why lots of guys have trouble.

Might have to check the local rent rite to see if they have the jig.
 

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What you need to know is axle flange to axle flange. Everthing changes depending on what brakes you use. Also different axles will change the measurement fom axle flange to housing flange. Even the axle bearings can change things. Check with your local race shop. They deal with this all the time. Mine charges $75.00 to narrow the housing. Have it clean and all the brackets that are not to be used removed. All your mounting brackets that are being used need to be welded on the housing first before the ends are welded on. This must be done with a tig welder and then no problems about welds breaking. A lot cheaper than building a tool to do the job yourself. I went with resplining axles and won't do it again. They screwed up on the length and would't stand behind there work. For a little bit more buy good street axles.
 

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rear end

:confused::confused::confused:

What does this JIG look like? Is it just a fixture employing a rod & vise?
MIG welding is a little cooler process than the others. The original fillet
holding the flanges isn't even flushed out. Stabbing in new flanges,
keeping everything plum thats all there is to it? Right?
quite being a tight wadd and spend 200.00 to get it done right. if you dont have the money where you gonna get it to fix the other issues that you will have with your rearend later.
 

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narrowing a rear housing

read cachassiworks instructions on taking measurements and ordering a housing the math dosen't lie it helped with mine and it was dead on just what I wanted brakes work wheels and tire clearance all perfect brackets and shock mounts all aligned perfect (S&W Race cars built mine for me) I just measured and measured twice gave them the info and they took care the rest axels bearings everything
look in my photobucket link at pics of my housing money well spent. Jerry
 
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