Thank you for your interest in OS LSD. It is unfortunate that several SCCA racers have had troubles with their OS LSD, but it should also be noted that we have sold hundreds (if not thousands?) of S2000 LSD worldwide for the past 10 years with very few failures (maybe 1-2 recorded instances outside the US); they are being used at all levels, from daily street driven to professional circuit racing. Analysis of the issue has pointed to the limited oil capacity in the OEM carrier as the root cause, and not a flaw in the OS LSD design. In order to aid in prevention of additional problems, OS has revised the design of the S2000 side gears. We do recommend use of an expanded diff carrier and/or cooler in order to keep the OS LSD properly oiled, but we understand that these modifications are not allowed in your SCCA class, and use of an expanded carrier/cooler is not necessary in order to use OS LSD.
OS LSD will be heavier than the Torsen diff; it is physically larger and denser. This will further reduce the oil capacity in the diff case so it is vital that the carrier is filled properly to capacity. Shipping weight for S2000 LSD is approx. 25lbs, I do not have data on the Torsen diff weight.
Installation is the same as replacement of the factory diff, please refer to your FSM for details.
Break-in is not necessary; for new OS LSD there is a bed-in procedure between the side gears and pinion gears but this will occur naturally as you drive; first oil change is recommended after one event or a few hundred miles; subsequent changes at the standard recommended intervals is fine. (15000+ miles?) Most pro teams change fluid after every event. We have endurance tested OS LSD on OS oil at Nurburgring for 30hrs with no fluid changes and no issues (Lexus IS-F). We have also endurance tested OS LSD on OS oil for commercial use with over 100,000km logged, also with no fluid changes and no issues. (Toyota HiAce)
Regarding settings, the standard setting is recommended to establish a baseline for performance. Should you feel the need to increase/decrease lock timing progression, this can be done by changing the springs in the pressure ring to either quicken or delay the locking properties. This requires the LSD to be removed and internal parts replaced. The best setting for someone else may or may not be the right setting for you, depending on your vehicle setup, driving style, etc.
OS LSD is not like other clutch-type LSD; it costs more because it is built with better materials using higher-level manufacturing techniques. If maintained properly the OS LSD should never require any sort of rebuild. We do not even release specific part numbers for the LSD internals, as any sort of rebuild kit should not be needed and is not offered as an off-the-shelf item. If you do happen to have an issue with your OS LSD, we will of course support you as much as possible to determine the cause of the problem and supply a remedy.
OS LSD is designed to handle any type of driving condition; our customers have been using it for street, drag, drift, circuit, auto-x, rally, etc. We feel that as long as enough oil is supplied to the unit it will provide years of relatively maintenance-free and consistent performance.
You can read about additional information on our website: http://www.osgiken.net

1) The Carbonetic differentials are a direct replacement for the S2000 so no modification is required. Follow OE [installation] instructions.

2) The Carbonetic differentials have been proven in the racing environment but being a racing product there is no warranty offered for their differential. Naturally if there are any manufacturer defects they will be covered.

3) The Carbonetic differential is only offered in a 1.5 way and a 2 way. These ratings are industry standard and not a true representation of the actual ratio of the diff. The 1.5 way is realistically closer to a 1.2-1.3 way diff and it is what you would want to go with. The higher the number the more lock you will start seeing on deceleration.

4) We have seen multiple seasons out of the carbon differential with no issues. Its impossible to put an actual number on [the lifespan] though.

5) All parts are stocked by Carbonetic in the US and are readily available for you to purchase.

6) The differential lockup rate cannot be changes but the pressures can be adjusted by moving disks around and adding washers / cone springs. We do not supply any information on adjustment of the differential. This would be something you would have to do on your own of through your differential builder.

7) The Carbonetic differential although clutch style is very quiet and smooth on the street. The carbon on the disks gives the differential friction material for slip when needed and a greater lock when fully engaged then a traditional metal to metal differential. Street driving will have no chatter or annoying vibrations like any traditional clutch style differential.
8). I do not have weight comparisons. Maybe Ben [PuddyMod] can chime in on this as he builds them.