Do I need a custom LSD tune or not? That is the question!

The answer is, it depends.
All of our off the shelf tune Super Lock Limited Slip Differentials (US-SPEC) were developed from years and years of tuning experience on various cars. 80-90% of the time a lot of these different cars share the same pattern in terms of build. Most of these cars have simple bolts on making roughly 15-20% more power than stock and not much more. Therefore our off the shelf tunes are based on that power range with the use of either street or R compound tires. 
It isn't until you get in the 50-150%+ range of power increase where you would need to have the Super Lock LSD adjusted to suit your particular needs. That is of course assuming the vehicle will be for road course use. 
For Drag, Drift, or Autocross application, it would be advisable to have the LSD custom tuned from the start. There are some exceptions, but for the most part these particular disciplines require faster action to reap the LSD's full potential.
We are capable of tuning New and Used Super Lock LSD's. So if you are interested, please give us a call and we can get you situated and have a brief consultation regrading the changes that will be made for your build. 
These units are not user-end adjustable. Special tools as well as assembly requirements differ among units that make it challenging for the inexperienced. Our tuning parts are also not available for purchase.