Why are Exhaust ports 10% of Intakes?

413 said
If you look at very old engines the exhaust valve is generally always smaller tha intake. Basic thing they figured out long ago

I don’t think it’s a one size fit all I think there’s just so many darn variables. The shape of the combustion area desired RPM range, efficiency physical size limitations. I found this comment from somebody on another forum that I thought was interesting. From Speedtalk.com