Preheat your oven to 325°F (160°C).
In a large bowl, whisk together the flour, baking powder, sugar, and salt.
Add the egg yolks, vegetable oil, water, vanilla extract, and lemon juice. Mix until smooth.
In a separate bowl, beat the egg whites until soft peaks form.
Gradually add sugar to the egg whites and continue beating until stiff peaks form.
Gently fold a third of the egg whites into the egg yolk mixture to lighten it.
Carefully fold in the remaining egg whites until fully combined.
Pour the batter into an ungreased tube pan.
Bake for 50-60 minutes or until a toothpick comes out clean.
Once baked, invert the pan to cool completely before removing the cake.