This question is a very old post, but I'm going to go for it anyway.
I assume you mean Masa Harina or Maseca masa. I use Maseca Nixtamasa. This recipe gives me 100 % consistency (with corn tortillas, gorditas, and puffy tacos- same proportions for all 3):
2 Cups masa
1/4 teaspoon salt (whisk well before adding water)
1 1/4 Cups water
Stir together with a ...