You may have won this time....go on psp-inc.com click on tools and type in necessary information and that's about it.
Keep the inside flare roughly the entire Diameter of the port away from any walls of the box, and same with the outside flare against any trunk lids/hatches.
I'd suggest using 3-4 6" aeros for 10cfYa I tried that I'm on it now but I don't understand it. I need a box tuned to 34 and using 4 inch aero port and it's 10 cube box and says 2.2 flare port? Idk what that means.... I need to know how long to make the aero port