Erowid, I believe, has the appropriate ratio of tryptophan to add per weight of substrate in order to approximately double psilocin output. They also have a paper detailing addition of tryptamine to produce quadruple the amount of psilocin.
A note on tryptophan decarboxylation;
Use 454g tryptophan, 1150 mL tetralin, and aliquot 4 13 mL portions of acetone. Using the longest path-length condensor available setup a refulx system with an addition funnel. Place the tryptophan, a stribar, and the tetralin in a 2L RBF and add the acetone to the addition funnel. Pump ice-cold water through the condensor, add the first portion of acetone and commence reflux. After a timed period of 3-4 hours, add the second fraction of acetone through the addition funnel dropwise. Assure that there is a continuous supply of ice condensor fluid availbe. Repeat until all of the aliquots have been added and reflux for a total time of between 12 and 18 hours.