Bowl Blending?

Bowl porting gains;

It can gain a nice amount of power, but is combo dependent.
In a "In General" amount, it could gain 20 - 50 HP.
Part of the combo that needs to be looked at is cam, valve size and type, induction, etc....

Bowl porting is;

The area just under the valve. Picture it removed from the head. All that can be seen in the imediate is considered the bowl. This area is opened up to meet the valve sized and smoothed out to resemble a bowl. The valve comes out of the "Guide" which is ground down to increase the area to be smoothed.
It's best effect is the low lift to mid lift area, approx. to .500 lift.