Factory recommendations: Acceptable: 0.4 - 0.95 cu ft net volume sealed 0.3 - 1.2 cu ft net volume vented, Fb = 22 - 36 Hz Optimal Car: 0.65 cu ft net volume sealed 0.45 cu ft net volume vented, Fb = 27 Hz I notice that the optimal vented box is smaller than the optimal sealed. I was thinking going sealed b/c of space issues but if going ported will really be smaller should I do this. Im also thinking aero ports and need some information on how to calculate what size I would need to tune to 27 hz. Does anyone own an rl-i if so what kind of box is it in?