Subs facing forward?

[germanyt 10+ year member]

My current box sits on the shelf in the trunk subs up port back. Spun it around once to fire forward and lost all output but it only seals off about 80% of the opening.. I did forward fire my 99 grand prix though years ago and it was absurd. Too many variables to say if it'll work better in a certain vehicle unless you'd installed in that model vehicle before.