Differentials oil weight for racing application

[MECHANIC77]

Hi guys..! Over the time I've modified my 4 by 4 Rustler to be a real racing beast but now it's time to set it up with the appropriate diffs oil and I just need to have a good starting point because I know it will be impossible to shoot only one cannonball and sink the boat on the first try, so my question is, what should be a good starting point if we take into consideration that my local racing track is a short course track with three 180 degrees turns and a medium grip surface condition.


Any advice will be greatly appreciated.