LSD upgrade

[Dmacc]

Originally Posted by rsr552

What do yall mean by "twitchy"? That is the first time i've heard anything bad about LSDs on our cars.

Not so much about the LSD but moreso about its gearing. The 3.46 final drive normally comes with auto's, the gears are shorter but you have great acceleration. By twitchy I'm talking about how aggressive our torque curve is on stock turbos for the n54. With my 3.08 final drive I have a hard time of keeping my foot out of it, couldn't imagine myself with a 3.46 if it is as others say it is for their MT!

[ISLong]

Does anyone know anything about os giken and dinan lsd's? I've been speaking with turner motorsports about the OS Giken and it's supposedly the best out there. If I stay with stock gearing they are both about 3 grand after core deposit. What do the waverac's and quaife's run?

[rsr552]

Not sure if everyone saw this (or has experience with them), but MFactory is supposedly coming out with a solution where they made their own Ring and Pinion to allow you to essentially convert to a bolted LSD solution for MT 135i cars.

Plus their price for their own in-house LSD seems like a deal...though not sure how their quality / performance are.

[NORAGRETS]

does anyone know the gear ratio's and locking % that dinan uses in their LSD?

looks like it IS NOT a 0-100% lock LSD and may be similar to the stock unit, maybe 40-60% locking and 2-3 plates

[fredy]

For a great deal!!!!

http://www.1addicts.com/forums/showt...light=mfactory

[NORAGRETS]

reviving this...

has anyone gone with the OS giken Superlock OR the Giken TCD units?

[135Pats]

Originally Posted by Twhill19

reviving this...

has anyone gone with the OS giken Superlock OR the Giken TCD units?

That's the absolute top of the line....OSG units are beautiful. They are noisier and require more active upkeep, whereas a Quaife is going to more or less be install and move on with your life. But for maximum performance you'd be hard pressed to find better diffs.

[bitcore]

Originally Posted by 135Pats

That's the absolute top of the line....OSG units are beautiful. They are noisier and require more active upkeep, whereas a Quaife is going to more or less be install and move on with your life. But for maximum performance you'd be hard pressed to find better diffs.

disclaimer, don't have one.

That mirrors just about everything I've read about them. If I had the money and planned to keep my 135 long enough, I would go for one of these as I like to go sideways a LOT. If you want to drift, can't really beat an OS. If you just want better traction and day to day drive-ability, a quaife will not let you down and requires little to no maintenance - comparable to the stock open diff. Dropping the entire subframe to change diff clutches isn't cheap and takes some time to do.There are a few race prepped BMW's that use OS Giken you can google them if you care.

VAC Sells both (and wavetrac - basically a modified quaife) and will build them into your diff for you: http://store.vacmotorsports.com/vac-...als-p2324.aspx

I'd want a finned diff cover if you are getting a clutch based diff and plan to push it a little - they put out some heat and need to dissipate it so you don't cook your gear oil. But, good god are the covers that VAC sells expensive.

[NORAGRETS]

So in quality ratings:

1. OSG
2. Quaife
3. Wavetrac

?

[135Pats]

Perhaps bc it's a small sample size (what maybe 2% of global 135i owners fitted a proper diff to it?) but you don't see too many issues with the diffs people are using. Some complaints of drivetrain clunks when changing out of reverse, but if properly installed the Quaifes and Wavetracs seem to be holding up really well.

The OSG is extremely nice but doesn't have the same type of longevity. It's built for maximum lock and response, and needs to be regularly serviced with OSG specific oil.

I'm kicking myself for not picking up a used LSD on the forums a week or so ago. I really need to get this taken care of before single turbo time.

[NORAGRETS]

How about the OSG TCD unit?

[wanganstyle]

Originally Posted by 135Pats

Perhaps bc it's a small sample size (what maybe 2% of global 135i owners fitted a proper diff to it?) but you don't see too many issues with the diffs people are using. Some complaints of drivetrain clunks when changing out of reverse, but if properly installed the Quaifes and Wavetracs seem to be holding up really well.

The OSG is extremely nice but doesn't have the same type of longevity. It's built for maximum lock and response, and needs to be regularly serviced with OSG specific oil.

I'm kicking myself for not picking up a used LSD on the forums a week or so ago. I really need to get this taken care of before single turbo time.

A Lot of hearsay about clutch type LSD units "needing service" - who has actually changed the clutches?
All the BMW's with factory LSD units from the 70's-90's had clutch type LSD units. In M cars they lived about 100k miles; @ 100k miles any differential entire unit under heavy use is due for replacement / rebuild; the bearings and seals will be worn out. Yes they can go to 300k in the 5/7 series+grandma....... but lets compare only tracked e30M/E36M/E46M - I'm sure many have one of these in the garage also.


Are you counting HOURS (caged race car) or MILES (street car)?

If you count HOURS (caged trailered race only car) the reset interval for the OSG super-lok is ~40 hours of wheel to wheel racing depending on power levels. Internals don't wear out that quickly - the service interval for a ZF BMW motorsports / drexler LSD is about that.

The internal set of a Super Lok can be converted to TCD if desired; parts are avail from OS directly but unless you are running a 3hour+ enduro this will not come into play; the OS runs quite cool compared to other clutch type differentials; the BMW ZF units run very hot due to the clutch compound and design.

If you are counting Milage (street car) the OS unit will have a service interval of about 30-50k miles depending on your abuse. If you street race or drag race then that is your own enjoyment The OS is also set up from the factory mild; many discs are de-activated for street driving. If you wear out the activated discs and its time to re-set the internal stack can be re-configured to have even more lock up if desired.

OS is a very tune-able item; it's not for those who do not like to tinker.
fluid is also extremely expensive at $300 / case of 6L; the GTR and 911 crowd love them as they don't care about expense.

BMW has solved the Welded ring gear issue for manual 135/335 cars by selling NEW 3,08 gearsets at the dealerships.