Calling owners of turbos with LSD,s..

[Big Dave]

Hi folks
Im after some info on the characteristics of the LSD as factory fitted to a 944Turbo.

When driving your car,s out of a tight corner, does the diff / rear end seem to "grab" / scrabble.Especially when you apply some "extra" power...I dont mean wheel spin....But a form of snatching from the differential...

Or is it a smooth exersices...??? just as whith an open diff.??

 

[333pg333]

Dave, the standard 40% lsd is really not for what your use would require. That is to say, they were designed with just fast open road driving in mind. They are not suited to a car setup like yours driven hard on trackdays. They will basically fail as mine did after a rebuild. It is definitely worth considering getting something better for your useage. My mechanic put in a special 80% one into his '86 turbo that we get made up in Melbourne (by a company that supplies diffs and gears etc for Quaiffe and Ferrari amongst others!)and in one season went from mid field to right up the front. In fact he won our overall club championships. He credited much of his improvement to this lsd and also going to a s2 crown wheel and pinion, which you already have. If you are really serious about you track times I would seriously consider doing something about this. I am. The feeling is that instead of spinning wheels or waiting until you're coming out of the corners, you can apply the power much earlier and it just 'pushes' you forward through the corner. Lots of time made up just in the corners let alone helping during the braking process.
If you want to know more email me. pgarvan@bigpond.net.au
Patrick

 

[chrisg]

Dave

your man 333pg333 is correct, for serious track usage you need a dedicated LSD. I seem to remember reading an article sometime ago about a 968 track car that was road legal and used as a spare for a racing team (white car with purple bits on). They used to drive it to the tracks and then swap over if there was a problem with either of the race cars.

I'm sure this article was in P& 911 world and the car was raced in the PCGB championship.. Anyhow, they used a Torque biasing diff from the states and claimed it was worth 2-3 secs per lap - this was (and the specifics of their diff setup) the secret to their winning team.

C

 

[Big Dave]

Cheers chaps
The "scrabbling / grabbing" im on about happens at normal road speeds , On the road NOT track...Its probably doing what it says,, limiting the slip in the diff...+ instead of "slipping" its more agressively "grabbing".
As when i had it re-built i asked for it to be "upgraded" with slightly thicker plates....
I was thinking ,,??? maybee a change of oil might do it some good...????
Its done poss about 5K miles of good track use.....

I find its great on track....

I also found that when i fitted it ,the car had a tendancy to understeer out of the corners , as it was "pushing" more as ide applied the power earlier...[][][][]

 

[thingo]

The motorsport(80% that 333pg333 refers to) diffs do that as well, I have a shimmed g50 lsd(968gbx) and it does it also, I think you just have to get used to it on the street, hate to tell you but your 944 lsd won't last very long with those shims(very small plates), so it will stop grabbing, but it will stop limited slipping as well.
It is a bit disconcerting, but it does make you pay attention.

 

[Fen]

Yep, mine doesn't do it, but transmission is the one bit of the car that wasn't rebuilt, so I assume you are seeing it because yours actually works and mine is a bit worn.

 

[333pg333]

Yes that is the feeling you will get as long as it lasts Dave. I don't think I noticed mine had stopped working because I have pretty wide tyres and the KW's just HATE losing traction so I don't get much wheelspin ever anyway but only that the company is waiting on some more alloy from BHP means that I'll have to get it (stock) rebuilt and use it again.
P.I.T.A.

 

[carlmthompson]

Mine does it. A bit disconcerting the first time it happened as it was a bit of a sideways jolt-and-grab, but I hadn't really thought about why as i'd just considered it to be my poor throttle control!

The car also understeers quite alot for my liking, but I'm figuring as the front tyres are 5 years old, this might be contributing!

 

[Big Dave]

Thanks for the info fellas..[][][]
Youve put my mind at rest.
I thought the LSD was going bad....[8|][8|]

Maybee i should start to worry if it does actually stop grabbing....[8|][8|]