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Old 04-14-2011, 07:50 AM   #41
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My buddy just installed one last week, initial impressions make it seem very similar to oem. The real test comes this weekend, we'll be at buttonwillow, I'm not driving said car but I can report back if it fails in any manner. With a few hundred street miles so far it's nice and quiet and seems just like oem, install was also a breeze.
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Old 04-14-2011, 11:20 AM   #42
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Quote:
Originally Posted by 90R View Post
Dustin
can you weigh the OBX
It's about 16.5 lbs.
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Old 04-14-2011, 11:41 AM   #43
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Quote:
Originally Posted by donutbob View Post
My buddy just installed one last week, initial impressions make it seem very similar to oem. The real test comes this weekend, we'll be at buttonwillow, I'm not driving said car but I can report back if it fails in any manner. With a few hundred street miles so far it's nice and quiet and seems just like oem, install was also a breeze.
That is good to hear. How much power is said car pushing and how hard is it being driven?
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Old 04-14-2011, 11:01 PM   #44
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Guess what arrived in the mail today:


I'm going drag racing this Sunday, and then again two weeks from this sunday. I don't have time to install it before this racing event, but it'll be in before the next one so I'll definitely be able to give a comparison on it. I'm also pretty sure my current dif is an open one, but I'll find out for sure once it gets taken out. I'll probably take the obx diff apart tomorrow morning. Pics to come.
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Old 04-15-2011, 07:32 AM   #45
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I want the pumpkin from your old one!
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Old 04-15-2011, 11:36 AM   #46
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I want the pumpkin from your old one!
I'm just swapping the internals so I'll still need the pumpkin.
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Old 04-15-2011, 03:01 PM   #47
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Well I went to do the rebuild today, and everything has gone well so far. I would be done by now but I forgot to pick up some blue locktite, and will have to bolt it together tomorrow. But my impressions so far are good, except you definitely need to order the bolt/washer kit upgrade that was linked on the first page of this thread. The bolts were way over torqued, and the hex head on one of them was all fubar'd. I had to hammer my allen key into it, and took my time backing it out. The bolts are significantly thinner in diameter then the replacement ones. Also, the washer that came with the LSD are pot marked and of very cheap quality. None of them were cracked though.

What I spent the most time on was figuring out what washer combination I would put in. The company that sells the washers/bolts recommends certain combinations, but they were either higher or shorter then the stock obx washer configuration. The washers are curved, so I ended up just mimicking the stock configuration (from the bottom washer it goes Down, Up, Down, Up, Up, Up). I spent about 35 minutes on this part, because I really don't want to have to take this out. So I'm trusting OBX enough on their base configuration for this.

The gear work within the diff seems awesome. Very sturdy, and everything just falls back into place when reassembling it. It doesn't feel cheap at all.

Here's the pics:



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Old 04-15-2011, 03:36 PM   #48
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I'm conflicted on the washer configuration, so I just emailed the guy who sells the kit to give me some advice.
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Old 04-15-2011, 03:48 PM   #49
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I really hope this works out. I'd really like something that I could beat the crap out of for fun. I baby the torsen by never doing hard launches.

I would buy one of these, a 3.636 R&P and an "open" pumpkin to install it all, making the swap super easy. This may have just devalued the torsen.

Oh, then we can sell the torsens over on m.net
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Old 04-15-2011, 03:52 PM   #50
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its pretty easy ()()()()()()()())()()()()()()() come on!


do we know what the torque ratios are for these things?
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Old 04-15-2011, 08:09 PM   #51
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Quote:
Originally Posted by dustinb View Post
they were either higher or shorter then the stock obx washer configuration.
Those washers squish, you know that right? And were they too short or too long? As in the washers were loose once tightened, or there weren't any threads to screw in?
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Old 04-15-2011, 08:56 PM   #52
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I wouldn't trust what OBX had on the washer orientation. Incorrect washer orientation was one of the big issues I saw frequently on other Honda installs. I used this orientation
)()()( when I did one for a friend's civic. I also lightly filed and sanded the raw sharp edges from the end of the worm gears and edges inside the case. It's probably not needed but it made me feel better.
I'll be going the OBX route in my Miata as soon as I sell off the S2000 lsd I have.
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Old 04-15-2011, 09:49 PM   #53
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Originally Posted by curly View Post
Those washers squish, you know that right? And were they too short or too long? As in the washers were loose once tightened, or there weren't any threads to screw in?
I do know they squish, but there is a warning saying that they can't be too high. The guy has already gotten back to me and suggested a few combinations to try.
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Old 04-15-2011, 09:52 PM   #54
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Originally Posted by Braineack View Post
its pretty easy ()()()()()()()())()()()()()()() come on!


do we know what the torque ratios are for these things?
We have no idea.
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Old 04-15-2011, 09:54 PM   #55
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Can you post the guys email response for future reference?
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Old 04-15-2011, 09:59 PM   #56
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Quote:
Originally Posted by djp0623 View Post
Can you post the guys email response for future reference?
Good idea. Here it is:

Here is my question:
I've torn the thing apart, and I guess I'm having difficulty trying to understand how to get the height right on the washers. My obx diff had 6 washers in it, and came in this configuration (if looking from the top down, I am starting with the very BOTTOM washer): )()(((. So it is in the combination of down,up,down,up,up,up. I'm really torn as to how to configure this. If I go with your sites recommendation, it seems to end up higher (if using 6 washers, even with the two top washers facing the same direction.

Could you please give some clarification on this? Should I just follow the OBX configuration? Thanks for your time!

Reply:
Dustin,

I wouldn't use the OBX configuration it really forces 3 washers to do all of the work. Additionally my washers are thicker so they are taller when you stack them (((

If you visualize compressing a stack of )()((( stack the right side of ((( is 3 times stronger than the left side so it just won't compress.

Here is some math. It is interesting to me but might bore you. If you don't like it just skip to the bottom bold sentences.


Given that configuration I would expect their stack height to be something like 9.9mm (assuming their washers are 1.2mm thick and 2.15mm tall)


My washers are 1.5mm thick and 2.15mm tall so...

I would probably try a )()() configuration. (that makes it 5*2.15mm = 10.75mm) so it is slightly taller.

It does however use an additional 2 washers that can compress.

We want between a 25% and 75% compression....

My compression height is (height - thickness) which is .65mm each. = 5*.65mm = 3.25mm
Assuming a 50% compression 3.25mm* 50% = 1.625mm
Assuming a 75% compression 3.25mm*75% = 2.4375mm

Their compression height is .95mm each = 3*.95 = 2.85mm
Assuming 50% compression 2.85mm * 50% = 1.425mm

Soooo the overall heights would be.......

9.9 - 1.45 = 8.45mm

10.75 - 1.625 = 9.125mm
10.75 - 2.4375 = 8.31mm

So if they were around 50% compressed then the )()() config should work for you if they were compressed more than that then go with )()((


Just count your turns from the time the case is suspended by the washers until the two halves touch (just touch not torqued to spec). If it is under 2 turns on the bolts then you are good. If they don't touch or it takes more than that then I would go with a )()(( configuration.

-Rich
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Old 04-15-2011, 11:25 PM   #57
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^???/ so confused. basically there will never be a cheap/simple solution to get me into the LSD lifestyle.

Last edited by samwu8k; 04-15-2011 at 11:42 PM.
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Old 04-16-2011, 12:38 AM   #58
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What doesn't make sense? Buy the $270 OBX LSD diff, the $32 washer and bolt kit, skip the math of the above post and orient the washers as described, reassemble, install, done.

What part of a $302 diff is expensive?
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Old 04-16-2011, 12:40 AM   #59
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Quote:
Originally Posted by curly View Post
What doesn't make sense? Buy the $270 OBX LSD diff, the $32 washer and bolt kit, skip the math of the above post and orient the washers as described, reassemble, install, done.

What part of a $302 diff is expensive?
No kidding, that's what I'm thinking. No more "Want my torsen for $700?"

Not that I really need one, but I've spent so much money already, what's another $300 when I swap gears.
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Old 04-22-2011, 01:44 PM   #60
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Just and update. The diff is going in Tuesday, but I might not get the car back until Wednesday. Normally if I didn't need my car I would just do it myself, but I need the minimum amount of downtime.
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