Quote Originally Posted by SeraphimXI View Post
Rank gives you some automatic stats and a feeding opportunity. You can feed your racing choco once per rank for bonus stats. They eat the new choco foods tier 1's give +1 to the stat, 2's give +2 and 3's give +3

Also at rank 40 you can retire them to use for breeding to get higher pedigree chocos.
Where would I go for said upgrade bentbranch?