rear speakers in new box = bad bass

in an ironic turning of events, a friend of my brothers was using out shope to re-appolster his arm rest for his truck, and he happened to have some polyfill, so i used it, and although it didnt make a huge different, the different was noticable, you could almost hear the speaker gasping for more air, so i removed the foam and stuck a couple holes into the box and its given it better bass already, but i wanna get a bigger bit, or etch out the design i was thinking of, 1 letter at a time to see if it needs more air each time i finish a letter. i checked the speaker holding it in the palm of my hand and it even sounded worse than within the stock box, god i dont know what i've gone through the trouble of making the box's they were fun to build, but the fact that i may end up with a skeleton of a box to even resemble working stock baffle, baffles me ;p owell it'll chalk one up for experiance tips 40yrs from now -_- ;p