Hope the image shows now.
bottom 2 pics whats that called ???
Leave the griding tool aside....ha ha. You need to know what to do.It is not like you throw some supra valves inside and job done or unsroud the wall around the bigger ex valve. Thats why some people report 0 gain from bigger valves. It is not the valve itshelf .It is kinda or recipe.I already told you a part of the recipe by email.Follow the instruction and you will be good to go...If anything additional just let me know and i will try to explain better.
Chris