Oddjob

Us PCA stock class racers dont really have enough power to worry about cracking the LSD housings. Going through synchros and wearing out pinion bearings is about the extent of the fair wear and tear we can put on the 016 transmissions with sub 300 bhp. The stock LSDs tend to hold up reasonably well for our racing applications.

samluke

I opend up the LSD and measured everything. As exepcted it was immaculate. No measured wear, no marks on anything, including the ramps.

So much for the myth that the factory LSD's are weak and wear out quickly.

951_RS

Nice wanna sell me it
No LSD is a curse on these cars as far as I'm concerned.

JDS968

Holy crap you need a macro lens!

Anyway, sorry if this is thread jacking...but can somebody explain to me why you guys seem to prefer the clutch-type LSDs so much over the Torsen-type ATB differentials?

alxdgr8

Most racers want lock up under accel and decel. From what I know, most Torsen diffs only lock up under accel.

ninefiveone

Google is your friend here. Short version: Torsens are great for street usage. LSD's are a much better choice at the track.

JDS968

I already know that, I'm asking WHY this is.

Okay now we're getting somewhere...

So why do you want lockup under deceleration? Doesn't that drag the outside rear wheel and hamper turn-in?

gt37vgt

well the to much lock may hamper turn in the balance is enough lock to stop the inner rear locking and from a few accounts poeple say a bit of decel lock makes the car a bit more stable while deep and hard on the brakes .
I'm a bit of a rouge .. I'm hoping that adresssing the rear tow and camber curves i can make the car as stable with a torsin diff.
Ah now i see it apart again you could simply have a tool room grind the ramps for accel lock up 1 or 2 degree shallower for more lock up..and probably need to case harden it again..

JDS968

Locking under braking?

Isn't that what ABS does? Because I'm pretty sure it's not just people with non-ABS cars who prefer the clutch-type on the track. Or is the point that the ABS pulsations are too destabilizing?

I find this whole thing very interesting

ninefiveone

Not trying to be difficult. Googling this will but much faster and educational rather then having folks try to explain it to you here. It's not a short answer and everyone can play back and forth on this board for days while you figure it out or you can get it all in 30 minutes.

savvas944

Actually 80% is not a black art.SAME Discs are to be rearranged within the diff,for more lock up
Also if needed a 968 Leman version check the 928 s4 lsd diff,10 discs instead of 6,and the caps interchangeable with the 944 ALSO.
need higher lock up,put 2.1 mm friction discs,instead of 2 mm.
Torsen type ,are useless in decelerating for track cars,have 2 Quaifes.