you say your space is 4x4 what hight you got in there? are you using both lights for flower or just the hps? with the 4x4 i wouldnt veg any more than 4 weeks cause they will full that space damn quick.top44 is a bad plant for stretching and has loads of leaf but nice hard buds.The light cycle would be 18/6 veg and 12/12 flower.the hight of the light depends on the reflector you are using but its usually around 18 inches but try putting your hand at the top of the plants and if you feel it burning then its to close. will you be using both of them lights for flower cause you would be better with higher wattage hps but they would do the jobthe postman.