Preheat your oven to 170°C (340°F).
In a mixing bowl, whisk together the egg yolks, 75g of sugar, vegetable oil, water, and vanilla extract until well combined.
Sift the cake flour, baking powder, and salt into the egg yolk mixture. Mix until smooth.
In a separate bowl, beat the egg whites until frothy. Gradually add the remaining 75g of sugar and continue to beat until stiff peaks form.
Gently fold the egg whites into the egg yolk mixture in three additions, being careful not to deflate the batter.
Pour the batter into an ungreased chiffon cake pan. Tap the pan on the counter to remove any air bubbles.
Bake for 40 minutes or until a skewer inserted into the center comes out clean.
Invert the cake pan and let the cake cool completely before removing from the pan.