diff ratio's

[layotn20]

sorry about this guys/girls, i know you have covered this many times before but i just cant seem to work it out

i have a fireblade 919 indy and need to know what diff is in it the codes on the diff are as follows 838g-4030-6a) or sumit like, as few digits are hard to read.
another code on there was (004ba)
the car has a reg mark aswell and old log book to a 1990 g reg sierra saphire lx 1998cc if this helps.

any help would be great