So I just bought my new car, a toyota celica, and I am going to have a custom box built for my q 18. with a kicker zx750, how many cubic feet should I go for? I am looking for a flat frequency responce and a good balance of sq and spl. I know these are all really rough terms but I just could use some advice.

Go the biggest you can basically. A Q18 is doable in a 4-8 cube sealed box. The larger the better, so take measurements. If you can't fit 4 cubes in your Celica then go with a Q15. 2.6 cubic feet isn't much at all....

Edited July 29, 200817 yr by chad

the bare minimum recommended box sizes won't give you flat responses either.

Are you looking for sealed or ported because a ported box for that is 5-10 cubes.

IF you go ported, you're gonna need almost all that room so u can tune very low to attempt to get a smooth response.