Dar, the link is for 4- strokes, and lacks valve cam timing input possibilities..
With two strokes, timing is more complicated, and must take into account whether you hace rotary, piston, or reed induction.
Also, the Bowling & Grippo guys have their facts wrong (in the text). The result is OK though.
A suction wave is reflected as a pressure wave when it meets an open ended tube. So in very short tracks, the wave is bounced back to and fro, until it eddies out. This is the least critical, but causes blowback at low rpm if the piston or disk closes late.
Full length, or 3/4 length tubes work better, but are critical at rpm below resonance.
Injectors (active fuel injection) should sit as close to the crankcase volume as possible, carbs (passive injection) should be as far away as possible.