Gerg is right, Vizard is a head working legend. When you get right into his head work you realize HOW smart he is. He was into 2L pinto motors in the 70's. It's not all about just grinding stuff out, any dill with a die grinder can go that... And muff it up. It's about the approach angle of air and velocity at the back of the valve. Sometimes metal or resin is added to the port to change the approach angle of the air. Then you want to go further its valve relocation. That's how it's done properly. Sent from my S21 using Tapatalk