From the begining question that you have asked the members here have given answers. The main responce has been that the correct enclosure size will matter more than how many/size subs. You have posted above you have had bad luck in the past, don't continue in the same direction. It takes more than some subs and an amp to attain what I beleive you are looking for, and the responces above reflect that. As ///M5 stated: "Again, post your space first BEFORE any other questions. Without knowing there is NO answer. Install is everything." Then Sir Lancelot stated: "You WILL actually get some help around here, but it is up to you to give us something to work with. The more specific and detailed you are, the happier you will be in the end!!!!!" Start with what you have and were you want to go, then it will be easier to help fill in the blanks and add to them...