OBX 413 spacers and installation

[Dave]

Christian Grest (Bubba) and I got onto the topic of the OBX for the 413. He noted that I need a steel spacer for the LSD. A quick search on TD showed that a guy here made them, but only 7 of them. I remember now that my brother machined Rob a spacer for his Quaiffe. After doing some looking I see Cindy is selling them for $275.

Does this mean I've now spent over $475 for the posi, longer bolts, Bellville washers, and Chris's tech to check it over, only to have to pay an additional $275 to make it work?? If that's the case than I'm scrapping that idea.

Thanks for any help.

[zin]

From what I understand, yes you will need the spacer, but I seem to recall that the plans to build them were floating around here somewhere, so you could see if a machine shop could make it for you for less. It's a pretty simple piece for a machine shop to produce. I plan on making my own, or having one made whenever I get to that point.

Mike

[TurboGLH]

If you want to use it in an auto, then yes. Either pay the $$ or get your brother to make another.

[Dave]

If you want to use it in an auto, then yes. Either pay the $$ or get your brother to make another.

I PMed the guy from TD that was building them. He said he still has a few left over, that was a month ago. My brother made one for Rob like 3 years ago when he was a senior in high school. He now works as a machine shop. But I doubt if he'll have enough time to make something like that. Anyone got the specs on it? I'm not sure if my dad will let me take his diff apart to use for a template just to fab up a spacer of my own.

[looneytuner]

Here's the original with credits. Note you also have to grind clearance inside the bellhousing and enlarge the diff cover by cutting knocking it out a little and rewelding the cuts.

The original price on the ones I bought were $90 including the cap head 12.9 bolts. Note the person that made them did so at cost without a labor or profit markup. Glad I bought two.

These had two sets of holes because of concerns about the stress on long bolts. The third pic shows the two sets of holes with the cap heads installed.

[Dave]

Sooo... do you have an extra good one then? Give yeh $100 right now.

[Speedeuphoria]

Does this mean I've now spent over $475 for the posi, longer bolts, Bellville washers, and Chris's tech to check it over, only to have to pay an additional $275 to make it work?? If that's the case than I'm scrapping that idea.

where have you been? its been discussed completley here and td.com. Need the spacer then new diff bearings/races and shims to set the preload. Grind the case for clearence, and cut/reweld the cover to fit.

[turbovanman²]

Bryan, you know I've covered the install in great detail, and with pics.

Whatever design I bought, it works perfectly.

[Dave]

I've never looked into those OBX threads as I never thought of getting one. Simon I'll search your name and see what I can come up with on threads.

Okay did some reading. What does it mean to preload the LSD? Rob's obviously going to help me install this so he knows what he is doing. I just need to know what parts I need to gather to make it complete. I ordered the posi, had Chris's tech inspect the LSD, chase the threads, and install stronger bolts, and ordered the Bellville washers (WTF are they for anyways??). So I also need the spacer and the longer bolts for the spacer to the ring gear, yah?

[turbovanman²]

I added the preload to my FAQ, which I moved to the FAQ section.


You need allen headed bolts to secure the ring gear to the OBX then use the stock bolts for the OBX to the spacer.

I am looking at getting some spacers made tomorrow and will post up a price.

[87glhs232]

and ordered the Bellville washers (WTF are they for anyways??).

They preload the sungears (axle gears) inside the LSD. They basically act as springs pushing the sun gears away from each other and into the case halves.

[Vigo]

What does it mean to preload the LSD

PROBABLY but not definitely referring to preloading the differential bearings themselves, not the internals of the obx. standard fare for any diff swap, just tedious.

[Dave]

I added the preload to my FAQ, which I moved to the FAQ section.


You need allen headed bolts to secure the ring gear to the OBX then use the stock bolts for the OBX to the spacer.

I am looking at getting some spacers made tomorrow and will post up a price.

Wait a minute, I was told not to use the stock bolts for the spacer to the ring gear as they are not long enough and are more susceptable to cracking.

[looneytuner]

The spacer was made 2 ways. Mine and Simon's has two sets of bolt holes for reg length bolts. The other design had one bolt going all the way through and requires the longer bolts you were told about.
The 3rd pic is Simon's, the Moose Motorsports drawing is the one bolt style. The PDF file has the name of the co that has the 12.9 cap heads for Simon's

[Frank]

Here's the original with credits. Note you also have to grind clearance inside the bellhousing and enlarge the diff cover by cutting knocking it out a little and rewelding the cuts.

The original price on the ones I bought were $90 including the cap head 12.9 bolts. Note the person that made them did so at cost without a labor or profit markup. Glad I bought two.

These had two sets of holes because of concerns about the stress on long bolts. The third pic shows the two sets of holes with the cap heads installed.

So you have used this design without problems?

[looneytuner]

So you have used this design without problems?

That's what DBBmini based his on. He decided on two sets of holes with cap heads in the recessed holes. Simon is using DBBmini's spacer. He blew the ring gear and shattered the trans housing and the dif and DBB spacer were still good.

Mine are still sitting. Money and time and a torn up shoulder and right arm are restricting my activities for the past 7 months.

And I noticed the drawing says "no reproductions without permission" after I posted it. I pm'd him here but he hasn't been on in 12 months. I don't have his email so I hope he is a nice guy and doesn't stomp me for reposting it.

[Speedeuphoria]

I have a 24 hole spacer as well, a guy at work made it for me, he looked at the drawing, and I gave him my stock diff for refferance. I turned it down a little more than when he gave it to me because I had to grind so much off the case, and wanted it to be an easier fit. I used stock bolts up top as it was easier to grind them down for better clearance as I saw from looneytuner, then socket heads for spacer to ring gear.

It used the small bearings/races on both sides(like the stock TD a413, cant use the larger neon diff bearings/housing). preload set as per atsg ~.008" preload

[turbovanman²]

That's what DBBmini based his on. He decided on two sets of holes with cap heads in the recessed holes. Simon is using DBBmini's spacer. He blew the ring gear and shattered the trans housing and the dif and DBB spacer were still good.

Mine are still sitting. Money and time and a torn up shoulder and right arm are restricting my activities for the past 7 months.

And I noticed the drawing says "no reproductions without permission" after I posted it. I pm'd him here but he hasn't been on in 12 months. I don't have his email so I hope he is a nice guy and doesn't stomp me for reposting it.

Yeah, the pinion let go but the ring gear was still tight.

I would prefer the double bolt hole design.

I thought the blueprints said reprint was ok, but changes not?

[Dave]

Man I'm confused. I hope Rob will remember what to do.

[Dave]

Ok I've PMed DBBMINI and james_13021 on TD for the spacer. Is there anyone else that makes one out there besides Cindy? DBBMINI is never on though, does anyone have a direct contact with him?