head porting theory q

[Froggx]

Looking at the head porting guides, on the exhaust side, it is suggested to grind down the lumps around the valve guides in the ports to increase flow for boosted/top end applications. Nothing is mentioned about this on the intake side. I assume this is because doing so would hurt performance. Could someone explain to me why this would be so?

[TheProfessor]

what kind of heads are you talking about

[Froggx]

3100/3400, guess I forgot to mention that since I thought it could be inferred from the fact that those are the only heads on the site with a porting guide.

[TheProfessor]

well sometimes the shape and contours of the port are more important than its size
im guessing it would have something to do with that