If you are speaking American English, “race” is a function of skin color, and believing one race to be superior to another verges on being an apikores since you are throwing into doubt the ikar in Humash that HaShem created everyone quite recently (Yaakov Aveinu was aquainted with the son of the common ancestor of all people). That’s make you very close to the “multiple creations” idea embraced by some goyim which is clearly apikorsis. If we are descended from a common ancestor who lives only 150 generations ago, all humans should be genetically close to identical (which, BTW, is what DNA analysis suggests).
If you are speaking British English, “race” is just a function of ethnicity and culture, and at most regarding other “races” (Americans would say ethnic groups) as annoying is quite rude in mixed company.