jaynanspl

Here is another way you could do it, I know it don't have the port in the middle like your wanting, but it might help give you some more ideas.

This is what i have come up with for you, was not sure if this is what you had inmind.

Do you have to have it at the 70" width?

Are you having any flex issues? Window or Roof?

I did not know for sure what you were putting this in, and what tunning you wanted, but this is what I came up with using your info. Hope this helps Jay

The Dual 2 for that, so you can run it at a 1ohm load.

What tunning do you want for you box?

Here is a quick sketch of maybe what you are looking for. The box is tuned to 32hz. The 3 round ports are 6inch by 16.75L. You said you were looking at maybe round ports. Good luck!

What amp do you have to power the 18? Do have a tunning choice. That sub is recommended for a 28hz box. Do you need it a little higher.

How much room do you have to work with? exact measurement would help.

I thought this might help. i did not know if you have built a box like this yet. i tuned it to around 32hz.

It is a little on the narrow side, but i still ended up with around 13cb ft after everything.

Just a few new pics of my install.

It may look a bit ruff, but your ears won't know the difference.

As for the overheating issue, they get a little warm do to the fact i'm running them at 1ohm. They are the Bl's. It was a little of a tight fit but i made it work.

As far as overheating no. They

Maybe this will give you some help.

Are they 15's or 12's?

How many subs are you going to run?

I have a question if anyone can help answer it. this is the problem i'm having. i have 2 of the fi 18 bl's. i'm running them with 2 of the mtx 7801d amps. 1 per sub. this is the part that gets weird. i have all thing hooked up but not the remote wire to the amps yet. the subs start freaking out. when the gains and the db boost on the amps are turned all down the subs still move a little without signal from the deck yet. as soon as you start to increase the gains the subs do it again. like i said NO signal from the deck. i have to use the db boost on the amps, because as soon as i hook up the bass knob the subs freak out. i'm kind of lost. when i have hooked up the remote wire to both amps things get a little strange. both gains are all the way down. i slowly start to increase them and the subs start to move without volume even up on the deck yet. i have thought of just taking everthing out because i thought maybe both amps were bad.i'm not sure if anyone can help. i just need a little push in the right direction Thanks Jay.

Just a few starting pics on the new build. Please tell me what you all think. This is the future home of 2 bl 18's. I have 2 mtx 7801d's. 1 per sub for power right now until i can get bigger amps.

I HAVE A 92 MAZDA 2600I AND WAS WONDERING IF THEIR ARE ANY HIGH AMP ALTERNATORS THAT WILL WORK ON MY TRUCK?

Just placed my order on Monday. Scott got payment Wednesday. My 2 Bl 18's should be on there way shortly. I guess christmas is coming early this year Thanx Scott, and Nick for all the help with my choice. Have a great weekend, Jason

I'm going to use 2 mtx 7801's for right now. I want a rockford 4000.

This will be the first time for me using Fi. I got these options Ohm: dual 2 Cooling: yes Flatwind: yes Daily or SPL: Daily Universal: yes