[Pyrat 2]

Originally Posted by BlindGoldfish

What are the advantages of 3 or 4 clutch types over 2 clutch types?

Also, do Diffsonline product a product that is superior to PG to justify the extra cost? Do Diffsonline utlize the OEM housing for the differential? It looks like PG has a drain hole in theirs which would make swapping fluid convenient, but it would also key off BMW service that something was amiss and I still have 2.5 years and 50k miles on my CPO warranty. I don't know if I want to risk them knowing about anything.

The PG uses all new parts (wanna buy my old diff?). As far as which is better, can't say for sure. On paper they are comparable. Both companies will build the diff to spec (# of plates, ramp rates etc). Both vendors recommend periodic oil changes after break-in and then periodically thereafter. So making this easy by adding a diff drain is a nice bonus with the PG diff. Both vendors build diffs for professionally competing BMWs.

As far as warranty goes, the factory cannot decline a warranty claim because of the diff unless they can prove that the diff caused the problem. Not that it matters with respect to warranty but my local BMW dealer did my install of the diff.

AW325Xi sounds very pleased with Dan at DO. I was very happy with Jim Blanton at PG. Either way you can't go wrong.

[BlindGoldfish]

I think I've sourced a set of 3.46 gears with 8000 mi. on them from someone with a 130i in Belgium. He wants $400 for the gears plus another $150 for shipping. I have to see what the LSD builders might do in terms of dropping the price a little if I supply my own gears. I also need to confirm that these gears will in fact fit in a diff that'll go in my 330i.

[chaz58]

I wouldn’t do this without changing the gears too. Gears make a big difference!

In the US, BMW offers a “performance differential” for the older 330s changing the gearing from 2.9 to 3.1. This 6.5% difference gives 0.5 seconds off of the 0-60 acceleration according to BMW and to Car and Driver (for a 328/330 this would be getting close to 335i acceleration).

The e90 328i MT gear ratio is: 3.23. The gears from the auto 335i is 3.46 and from the auto 328 is: 3.91
I’m not sure where the 3.38 came from – the AWD 328xi MT has a 3.39 though.

[Pyrat 2]

Originally Posted by chaz58

I wouldn’t do this without changing the gears too. Gears make a big difference!

In the US, BMW offers a “performance differential” for the older 330s changing the gearing from 2.9 to 3.1. This 6.5% difference gives 0.5 seconds off of the 0-60 acceleration according to BMW and to Car and Driver (for a 328/330 this would be getting close to 335i acceleration).

The e90 328i MT gear ratio is: 3.23. The gears from the auto 335i is 3.46 and from the auto 328 is: 3.91
I’m not sure where the 3.38 came from – the AWD 328xi MT has a 3.39 though.

+1 on the gear ratio change.

Actually the perf package on the previous 330 had the following gear ratio changes:
MT from 2.93 to 3.07 = 4.8% change
AT from 3.38 to 3.64 = 7.7% change

I had mine changed from 3.15 to 3.38 = 7.3% and the difference is very noticeable.

[BlindGoldfish]

I'm going to bump this thread to let people know how awesome this addition is. I installed mine a couple months ago, but now am upgrading my car so the LSD is getting sold here:

http://www.e90post.com/forums/showthread.php?t=379326

$1,990 shipped.

[Pyrat 2]

Thought I'd bump this thread with an update. After more than 5 years and approximately 60k miles on the LSD it has continued to perform flawlessly. The car has been to the track too many times to count since it was installed and it has performed well. The diff remains completely silent with no noise whatsoever under any condition. The drain plug that Jim put in has made for very easy diff oils changes.

Being in the midwest it has also proven great in the snow. Along with snow tires the car regularly out accelerates many four wheel drive trucks (presumably without snow tires). For any one considering buying an LSD for their E90 my answer remains that the investment was well worth it.

[justpete]

Will echo HeelToe here, a PG diff is a solid investment. Only 18K miles so far and a good number of trackdays without a single hiccup. Very noticeable improvement from day one.

Had it geared up 15% to make the transmission a true six speed without overdrive, really improves road force at this ratio.

Ramps are symmetrical at 35% static, 70% dynamic for 2-way 100% lockup according to Jim. And four 90mm clutches per axle.

Worth every single cent.

[sinner-]

Originally Posted by Dr.Sommer

The 130i diff is fitted now. .....

To give you a picture what are the gains of the 3,46 at which kph, I've attached "wheel force diagram" for you to compare:

greets

Dr.Sommer, can you help me in a Private message with some info please?
I am looking for a longer 6th gear 'sproket' swap and it seems you know a lot abt gear ratios from other BMW models and i hope for a plug and play fit.

Sorry for hijacking thread form the LSD topic - thus the PM asking.