Still have excess heat issue

My indoor box 2 x 3 x 5 is still getting too hot inside ( 82-97 ) despite adding extra fans(inlet and exhaust). I new my 400hps would cause me probs but I just cant bring it down enough. I made an air intercooler by running the inlet pipe through a bucket of ice water, that didnt do enough, I have got a dehumidifier, that didnt do enough, 2 x inlet cmf's and 2 x exhaust cmf's, that didnt do enough, a 12 inch ossc fan inside, that didnt do enough, im still getting 85+ deg.

I have an outside brick shed 3 x 5 x 8 which I would prefer to use but I have no way of getting a fresh air supply into it.

I realy realy need some help. I have the seeds from Nirvana and everything else need but just cant crack this heat prob.

I also forgot to mention that I cant really upgrade the fans to bigger ones cas its in my bedroom and they already make a hell of a noise.

Mine are growing in my coal shed outside and i was having heat problems,i've just extended my cupboard upwards and now have the temp at around 79 all the time.What i found at first is i had to open the cupboard door to let some heat out,even tho i had a vent on top,a hole knocked in the side wall and some vent tubing into the cupboard and a vent on the door to let air into the cupboard.