The present disclosure relates to cordierite-forming batch materials and methods of using the same, and in particular batch materials for forming porous cordierite bodies suitable for treating engine emissions. The batch materials include sources of magnesium, alumina, silica, and high BET specific surface area raw kaolin clay. In some embodiments, the BET specific surface area of the raw kaolin clay is greater than 22 m2/g. In other embodiments, the BET specific surface area of the raw kaolin clay is greater than 13 m2/g, and the source of magnesium oxide and the source of non-kaolin clay source of silica both have relatively coarse particle size.