Preheat your oven to 325°F (163°C) and line your cupcake tin with cupcake liners.
In a medium bowl, sift together the flour, baking powder, and salt. Set aside.
In a large mixing bowl, beat the egg yolks with ¾ cup sugar until light and fluffy. Add the oil, vanilla extract, and water. Mix until well combined.
Gradually add the dry ingredients to the wet mixture, stirring just until combined.
In a separate bowl, beat the egg whites with cream of tartar until soft peaks form. Slowly add the remaining sugar and beat until stiff peaks form.
Gently fold the whipped egg whites into the batter, being careful not to deflate the mixture.
Fill the cupcake liners about ⅔ full with the batter.
Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean.
Let the cupcakes cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.
