Trouble keeping the new mylar tent cool

My original tent was much smaller maybe 3 x 3 x 5, all I needed was an intake and dual outtakes on either side of the tent. This worked fine for my small 250 watt air cooled digital MH light. As the temp stayed around 77 consistently all day until night when it would drop to about 69.

However, I recently installed a 4 x 4 x 7 tent while brutalizing x1 400 watt cool-tube MH in addition to a x1 600 watt cool-tube HPS, I have both connected to ducting and separate intake in addition to outtake fans and honestly the lights themselves are staying relatively cooler than my smaller 250 watt air cooled hood ever did, my problem I think lies with my intake, which is a insulated 6 inch ducting attached to 2 6 inch inline fans. Maybe this summer is just hotter? Anyways my question is how can I drop the temp from about 83 degrees to something more like 70-75 without spending hundreds of dollars on an AC unit? I'd say my budget is 200

Ur saying the carbon filter is on the intake? It should be on ur exhaust.
Filter>hood>(hood if your 600w and 400w are not sharing a hood)>out of tent. Or if you have seperate fans to cool your hoods and exhaust tent you would just mount filter at the top of your tent and exhaust out.

All your lower flaps open so the cool air comes in the bottom and pulled out the top? Some open to top zippers to cool but no air gets sucked in the bottom that way.

That was a typing error, thanks for catching that mnmobbin, yes the carbon filter is attached to my exhaust.
https://www.rollitup.org/members/coho-411723.htmlCoho: Yes and no, I keep the flaps unzipped to allow cool air from the room to flow in however at night when the temps drop I zip them up out of habit, should I try just keeping them open at all times?

How cool with all with all the flaps open? The problem with flaps is light leaks during flower. Make sure you suck air in from ground level as its cooler.

around 81-83