where is the thermometer placed? if it's in the dierct light then the reading will be a false high reading. put the thermo at about the level of the canopy and shade it with a peice of cardboard or something. 465 cfm should keep the temp in that size cab the same as the ambient temp of the room the intakes are in. i had a 2x2x2.5 aprox. cab with 150hps and 120cfl with a 180cfm ehaust ant 4inch duct fan for intake and the temps always were the same inside and outside the cab. that means that the air didn't have enough time to heat up before it was exhausted. remember the temp can never go lower than the temp of the air being drawn in (intakes) unless you are using an airconditioner. so if its 90degrees in your house in july then the lowest you grow ttemp could possibly be is 90 degrees(probably a bit hotter) good luck!