Is udayar and kulalar same caste?

No kulalar and udayar are not same caste parkavakula udayar (malayaman and nathaman clans) using this title from ancient cholas period parkavakula udayar(warrior and landlords) living around cholamandalam, but kulalar is an pot making caste they usually exist around western Tamilnadu they have title mannudayar ,they also sometimes known as udayar , this is the reason for your confusion