Ok thanks for that the soundstream engineer said 3cuft3 @ 40hz is the optimum size but it just didn't sound right but i found one that size and tuning for $50 so i guess i can't complain. 2cuft3 @ 36hrtz should make it sound a bit clearer or just louder? Either way any improvements is great. It would save me some money (not buying a new sub and box)and that will leave me more for new speakers and service my gear box etc. I could never work WinISD even with the TS specs it just says things don't match etc (something like that) So being told what size and tuning is a great help as a smaller size should allow me to build it into my wheel well.