Howdy, I have tried various settings of the Autodelta clutch type LSD in my supercharged GTA car over several years, as well as the Q2 diff for a year.
Sure, it does make a slight groan when a lot of lock is on at very low speed.
Its 100% perfectly normal! All clutch type diffs in a FWD car typically do this.
You can largely eliminate the noise by adding Redline friction modifier to the gearbox oil, 1 of the smallest bottles is plenty. You wont really hear the noise at all then.
However the diff theoretically has its optimal performance when there is a slight groan, the friction modifier does very slightly make the plates have a teeny bit less friction.
Thats the theory, but I couldn't really detect any reduction in diff performance myself.
BTW these difffs have way way less torque steer than the Q2 once you dont "jump" on the throttle , and also put the power down with much less drama. On track I reckon the AD diff would be worth over a second to the good as compared to the Q2 since it controls inside wheelspin so much more convincingly. There probably would be a smaller difference with a standard GTA, but the Q2 gets increasingly unruly and ineffective as the car becomes more powerful or torquey.
The Q2 or quaife are better at hairpins though with standard GTA power levels.
You dont really adjust the diff per-se regulary to change the locking % and preload, that would be very expnsive to do..
I'm not sure how long before it would need maintenance, but certainly at least a couple of years. I would guess at three years for road use.
Yes, you do need a higher locking effect, or tighter diff as you say, with a supercharger due to the huge increase in torque. A more aggressive diff setting does impact the level of "groan". As the power of my own car increased the diff was adjusted correspondingly.
The plus point is that your car is really well setup for track days now..
..and in the wet you would run rings around with anybody with a Q2, or quaife diff.
Enjoy your car, it sounds like a cracker.
My first post so bare with me on this one!
Just bought a 147 GTA off Jano at Autodelta. Can't tell you how happy I am with the car. I work for an Alfa Romeo dealership and thus have driven lots of GTA's but this thing is in another league!!
The car has had the LSD fitted, with the autodelta adjustable coilovers, engine remap, carbon induuction kit, cross drilled 330mm front discs ( with the braided hoses and AD pads ) 4 exit exhaust, AD super AM front bumper and black 18" multispoke off a GT.
My question is, the diff groans at low speeds round corners, is this normal or is it doing any damage? Jano and a few of the techs at work ensure me that this is perfectly normal, due to the fact the car was originally going to be run with the supercharger conversion, so the diff is set quite "tight". It doesn't really bother me, just want to make sure no damage is being done! Can anyone shed any light on this one?
The second thing was what kind of maintanence needs to be carried out on these AD diffs?
Many thanks for all your help on this one guys and girls
Here she is