Our hi-flow seats were designed with porting in mind. The top of the seat has a 30 angle extending all the way up to the outside edge. This is so the seat will blend right into the combustion chamber. These seats will not have that dropped in a hole look.
All seats have a radius on outside bottom edge to eliminate galling when being installed.
Existing seat pockets must be bored oversize before installation. Exact sizing on package. These seats were made .002 oversize so that they can be dropped right back in the stock seat packets without costly machining.