Not too long ago, a reader posed this question to me - why do my Chiffon cake recipes mention using a larger proportion of egg white than egg yolk?
Ah hah, that is a really good question!
I am not an expert in Chiffon cake so may I humbly share that in my experience of baking cakes, there is no right or wrong to use different proportion of egg white to egg yolk. It is also common to find recipes that use the same amount of egg white and egg yolks. However, my personal preference is to use more egg white than egg yolk, for the reason that the cake will turn out more fluffy and 'springy'.
Why? This is because when egg whites are baked at high heat, they tend to expand/rise/increase in volume better than egg yolks. That said, egg yolks also have their benefit too; it will solidify faster and hence 'hold' the cake ingredients together.
In summary, it is up to your preference the percentage of egg white to egg yolk for your cake recipes. For more explanation, please refer to the details I have attached below :)