Intro to a port job

66fs said
Most important is the seat. Grind just enough to clean up. Then adjust the position and width of the seat with the top and bottom cuts.

I cut the 45, top cut 30 for the 'valve' seat size, narrow the seat with the 60. Theres more than one way to skin a cat though.

a lot of places just touch the 45 on heads that aren't in too bad shape... or dealership work.