Based on your sealed side at 4cu per chamber. I'm gonna say you need to be tuned in the 47-49hz range. But of your tuned at 49 with our port out, I'd leave it there and play with it. Once th subs FULLY break in, slowing shrink port. Again I see you best results around 46-49hz tuning. I would shoot for a port size of 360-390 sq
Based off mine, which still needs a few tweaks. It's 7 cu sealed and 22.75 ported, tuned to 50.5. And that tuning was figured for brand new subs put the sub. I need to slightly lower tuning now.