Questioni was wondering will 2 15 inch L7s in a ported box fit in my 1989 nissan maxima?
Answerwell, this isn't an easy question to answer. I don't have a 98 maxima handy (although I wish I did, "nice car!").
But my answer will be how to tell for yourself.
Basically you need to find out how many cubic feet each sub needs. ported boxes are larger than sealed. and ported boxes can be designed larger or smaller depending on the sound you want from the speakers. a smaller ported box will be very loud and boomy but not very musical. a larger box will sound fuller and deeper and the deep bass will be louder and it will sound much more musical. so depending on your needs you can tweak that to make it fit.
looks like the 15" L7 is rated for anywhere from 3 - 6 cubic feet per sub. which sounds about right. at about 3 cubic feet you can port the box around 35 hz comfortably and have good sound, good output, etc. or you can port it at about 40 hz and it will be very loud but boomy and not too musical. but if you build the box larger, like around 5 cubic feet per sub you can port it at 30 hz and that thing will rattle your car apart and be musical! I have 4 12's ported at 30 hz and I literally blew the sunroof off its track, pressed it right out the top of the car!
So the first step is to realize your range and see what you can fit in the car, in that range, if you do the math based on the smallest size of 3 cubic feet per sub and that wont even fit, then you have to pick something else or go for a sealed box or something. if 3 cubic per fits fine then maybe you want to try 4 or 5.
so now for the math part.
basically we can start by measuring the maximum size box you could possibly get in there to see what we're dealing with here. so you have to measure your trunk and remember that you cant build the box to the exact size cuz you still have to be able to wiggle the thing in there when its done! unless you build it inside the car (not recommended)!! remember allot of cars have the ability to fold down or even remove the rear seats, so you may be able to get a much bigger box in that way instead of in through the trunk opening. That's how I did my wife's jetta.
so measure your length, measure your height, and measure your depth all in inches and like I said take some off if you can tell how the box needs to swing to get in there. remember the wood you use to build the box is going to take allot off what's left on the inside so subtract 1.5" off each measurement (.75 per side). Now just multiply all them together. then divide by 2 since you have 2 subs. and now you have a number in the thousands which is your internal cubic inches, so to convert to cubic feet you divide that number by 1728 and the answer (HOPEFULLY) will be within the 3-6 cubic foot mark for you.
here's an example:
40" wide
17" tall
20" deep
40 - 1.5 = 38.5
17 - 1.5 = 15.5
20 - 1.5 = 18.5
38.5 X 15.5 X 18.5 = 11040
11040 / 2 = 5520
5520 / 1728 = 3.194 cubic feet per sub
we really should have a center divider wall inside the box so that length really should've been 40 - 1.5 - .75 = 37.75 but oh well, you can do that yourself if you decide for or against the center divider. also remember you have to subtract off what the port takes up, we can get into all that in another email. first do what I've outlined here and see what we have to work with. then we'll attack the details.
Good luck and I look forward to hearing from you!
