kpeters0929

Just seeing if anyone can help me out with my previous post above. I added the overall max box dimensions. Can't wait to start the new system

Hello, So i'm finally deciding to change my setup in my '90 Regal and i definately would like to go with some BTL subs. I'm starting to plan everything out beforehand so i figured i'd ask your opinions first. I'm planning on going with a ported box and having it forward facing (blocking off the trunk.) So the rear seat would be removed. I calculated my max box size i can fit ... and it comes to just over 3.3 cubic feet. This is the I.D. of the box and the woofer has a .21 displacement so i'm at just a tad over the 3 cubic feet mark. Now FI recommends a 3-5 cubic feet box size. I plan on playing mostly hip hop/rap with big bass notes. Would i be fine with only having a 3 cubic feet box? Or is it mandatory that with bigger bass i'd need to go with the maximum box size which would be on the 4-5 cubic feet level? What exactly would i be losing out on by having a smaller box? My only other option would be to use (2) BTL 12" subs instead but i kind of wanted to go with the 15's. BTW i plan on powering EACH sub with around 2500-3000 max watts RMS. I have plenty of power to do it if your wondering... it'll have a dual alternator setup. Any help is greatly appreciated. Thanks!

Sometimes is not what you want but what you can fit in its right enclosure. Go measure the max dimensions you have to work with and then we can tell you what will be best for your car. The current OD of the box currently in the car is.. 34 3/8" wide for both speakers... so basically it is 17.1875 for each speaker. 27 3/8" depth 15" height These are including the slot ports. Without the slot port it would be 14 1/4" wide for EACH sub. The ports are 2.2" wide and 13.4" tall. I'm unsure how long the port extends to without taking the sub out.... but when i had the box made the builder told me he built it to JL's specs which were 2.375 cubic feet per sub tuned to 30 hz. The wood i believe is 7/8" thick. Now here are the overall dimensions of the new box i can fit in the car. These are OD dimensions INCLUDING the port. Stock i can fit... 15" height 17.1875 width 39 3/8" depth Now if i were to modify the trunk lid flip hooks the max i'd be able to fit are... 16 1/4" height... possibly 16 1/2". If i'd add spacers to the 6 1/2" speakers in the rear deck i'd be able to fit 17" height. 18 1/4" width 39 3/8" depth As for the towells i understand it's not the right way to do it, but i figured they worked because when the trunk is opened while the system is on, the bass doesn't increase or decrease in volume. Is that the only thing i'd have to fix in order to completely seal off the trunk? I really didn't know exactly how i were to go about fixing it since i couldn't picture how i'd put wood there.... i was planning on wrapping those holes from the quarter panels with Second Skin Luxury Liner pro (i have a bunch left over since i did the whole car.)

If you weren't so far away i'd tell you to drive on over and listen to my setup lol. Honestly i really do like the W7's compared to other systems i heard locally. To me they sound rather clean but honestly i don't think they hit the lows that well. Their are other factors why i'd like to go bigger/louder. W7's are non-reconeable which is the downside and not to mention the cost of them! Some say the W7's are more towards the SQ and i just want to go all out for next year. Probably do a couple competitions in the Chicago area, but i rarely see ANY trunk cars that get insanely loud. I did give an 18" single sub a thought but i'm leaning more towards having (2) subs either the 15's or the 12's. I'd have more cone area with 2 subs compared to a single 18".

Thanks for the replies everyone, I understand facing the subs toward the trunk should have the higher output, but for some reason it didn't in my car. My trunk sounded like crap and everything is dynamated. All i did was flip the box so it was facing forward and what a HUGE difference in output it made. I don't understand why but it definately did and the trunk doesn't make any type of noise whatsoever. Only thing i can think of is the current box was too big for the trunk? maybe? I didn't really "seal" off the trunk when they were faced forward. All i did is cut the back seat area perfect so the box kind of wedges in on the top. I included a picture below just so you can see. On the sides their are two holes which i stuffed blankets into. This was just a temporary fix until i had time to do it right. From the picture would you consider this completely sealing off the trunk? If i play a song and then have someone open my trunk the bass is not affected at all. Update on the FI BTL 15's though. I talked it over with the person planning to build my box for whatever subs i decide to go with and he gave me another idea. If i were to modify the factory trunk lid hooks (the hooks that flip the trunk lid up) i would have room to fit a wider and taller box. We measured it all out again and it would put me in the 4-4.1 cubic feet range PER sub and that is already subtracting the sub and port displacement. What do you guys think about that area for the 15's? Picture here for previous post.

Alright thanks guys. Yes the 3.3 cubic feet is PER sub. So basically i'd have 6.6 cubic feet including both subs. I currently have (2) 13w7's in a ported box facing forward. Tomorrow i will have some time to snap a few pictures so you can see exactly what i mean by having the back seat removed. Maybe then you can have a better idea of how they will be inside the car. But when FI recommends a 3-5 cubic foot box how do you go about which size would be correct? For example, if you had 1 15" sub in a 3 cubic foot box and then switched the box out to a 5 cubic foot box in the same exact car, what differences would it make... pro's and con's?

Glad you could join us , first of all that 3ft^3 is only after sub displacement (you still will have to factor in port displacement too, which is going to make the box even smaller). If you cant fit what you need then dont do it since it will be a waste of money and time, I would go with the 12"s so they can get all their required space. Just my .02 Thanks for the reply, Well i actually did already factor in the port displacement. Here is the rough dimensions of the biggest box i can fit PER speaker. Overall O.D. width - 17 3/8" including port Height- 15" Depth- 46" They are 15" speakers so i understand the height may be an issue since the biggest i can fit is 15" tall. I'm not sure if this would be an issue or not but i figured i can have the front of the box made a little taller by a few inches if needed so the face of the woofer will bolt up. They would be forward facing so it doesn't matter if the front of the box is taller.... but the rest of the box which would be inside the trunk can be no larger then 15" tall. I can draw a diagram if needed. Let me know your thoughts. I think this would be a great setup if i can get it to work!