Captain Carling

I've just bought a Quaife lsd for mine, and when we took the diff out, we found that it had 4 plates a side so basically it already is a weak form of lsd.
The car has not got the performance pack so should be an open diff really????

Basically, I'm just wondering if this IS an oem lsd?

Captain Carling

Mort

Sounds like an OEM LSD. Check your data card and option code 471 is for the LSD. There are threads here that Valvestud will run your VIN for you and post your data card.

Eric ATP

The performance pack has nothing to do with the LSD. You had a factory LSD car. It works well. The LSD did not come with the performance pack and it was a stand alone option.

m a x i m u s

From what I understand, LSD was part of my P30 package.

zcct04

Not necessarily true - depends on where your car was sold.

Merc63

You could order LSD without performance package. You have a clutch in it, that's the factory LSD, couldn't you tell driving it, both wheels spin the same?

Captain Carling

Only just bought the car and assumed it didn't have one. It sold quickly on ebay anyway so happy days

Diabolis

You mean - you replaced the OEM clutch-based LSD (which if you were so inclined you could have repacked to achieve different accel/decel lockups to your liking) and replaced it with a gear-based LSD? Why, mate?

Captain Carling

The stock lsd only has a four plate system which is a weak lsd. The Sierra Cosworth had a seven plate and the Mitsubishi evos had eight. That gives you an idea of how effective the AMG one is. Not saying it's a bad one, but not the best

roadtalontsi

and im sure the cosworth and evo's had the same size differential. more plates = more surface area if the plates are too small. It's funny you mention those cars when neither needed limited slips. Not to mention evo transmission blow up regularly with anywhere close to 500hp. If you didnt feel it working, it may have just needed fresh fluid.

Captain Carling

They are cars I have had in the past and yes, they did need an lsd

Diabolis

You could repack the diff and/or rearrange the order of friction & metal plates in order to change the lockup ramps. And, the number of plates has nothing to do with the amount of lockup, preload or the longevity & durabilty of the LSD. All of the serious Porsche Cup car and RSR LSDs were four-disc, as are most of the Guard Transmission aftermarket racing units that we've put into countrless GT3R competition cars. Do the plates wear out? Sure. Do I want to give up the option to have it set up to my liking as well as completely give up LSD lockup during deceleration which is how gear-based units work? Not a chance. Just my $0.02.

Captain Carling

It has been done now, so I'll give some feedback when I've been out for a blast

Diabolis

For street driving and drag racing, you are probably going to get more benefit from the Quaife (or any other gear-based diff) - you'll get a bit more lock-up on acceleration than with the OEM MB unit, plus gear-based diffs are not wear-and-tear items. Unless you're a regular track (circut) driver, you haven't really done anything detrimental.

I agree that the OEM MB LSD is very mild - but a set of slightly thicker custom plates that will you give you a proper 40/60 lockup is about $600 IIRC. When I repack mine I use two even thicker plates (the ones with the external teeth) and without changing the preload I probably get about 50/70 (or maybe even 55/75) ramps. I woudn't recommend this for regular street driving - to the average driver it makes the rear end twitchy, but that's exactly what you want to get it to rotate on a circuit.

Let me know how you make out and what your impressions are re the handling of the car.