Port through the rear dash?

hey, you know i had the exact same idea for my car, (94 cavalier) but keep in mind, you have to ask yourself whether your going to sell the car in the future or keep it for yourself...putting holes in the rear deck will lower the value of the car, BUT, if you insist of making the project, then here it is, oh and if i made any mistakes please feel free to correct me or give ideas everyone..... above everything else, you have to make a box (duh), make the box acording to the subs box specs for ported, but don't cut the holes for the ports yet (on the box), install the subs, and put the box in the trunk, and secure it down, once that is done you have to messure where the ports are gonna be placed and then take out the box...to give an idea, and good sugestion..if your gonna be making ports, make a square port instead of a round port, you'll get alot more air travel and less port noise, build a big ass port. but look, messure and see where your port is gonna be going...especially in the inside of the car, mark out an outline, and then cut the hole (from the inside of the trunk, it's really frustrating to cut the port in the inside of the car, plus it's messy). you might wanna make the port a flanged port too. fit the port in the hole but make sure your port is snug too and leave some carpet over hung onto the hole and then put the box in the trunk again...mark an outline of the port and cut the hole, but remember the port has to be long enough to go through the rear deck and into the sub box. once that's done cut the hole for the port, bla bla bla, lol. spray paint the port so that it matches the rear deck..next put the port through the rear deck, and then put the sub box in, now you wanna REALLY secure the port to the rear deck, by placing L brackets from the underside of the deck to the port and the same for the sub box, make sure the port is really secure and you have to secure the sub box too..you DO NOT want the sub box flying all over the trunk it'll wreck your project. but other than that its pretty simple. i was gonna do this project, but i thought naw it'll just wreck the car, so i just detached the back seat so i can make it fold up and down, and plus this way there's ALOT more db's than doin it with port in the rear deck. and if i wanna sell the car, i can just re-attach the seat. it's alot louder with the seat down :) good luck

You have 2 options

1) Use a sealed enclosure and port the rear deck. If you cut a whole in the rear deck to let the trunk breath it is the same thing as putting down the back seat. To do so you will want to remove the rear deck, cut a whole to the desired size through the sheet metal of the car. Once you do so put the rear deck in place and mark the underside where you cut out your port/vent. Then remove the rear deck and cut out where you marked the cut out for the rear deck vent. Now you should have a port between the trunk and the cab. Once you have done so I would suggest that you cover the rear deck in dynamat and put large furniture foam pad in between the rear deck and the rear deck cover to stop it from vibrating and give the cut out some strength. To finish it off and to give it a nice professional look, build your self a speaker cover and cover it with speaker mesh the same color as the rear deck. Option 2) Go for the ported enclosure and have it go directly through the rear deck. You will want to build a port that extends out of the box and ends at the top of your rear deck. It’s pretty much the same instructions as above except your using a port this time.

Frito you do really excellent work.  It looks like you did it all at your house too.  Most so called professional installers in this town with a full garage can't do custom jobs like that.  Keep up the good work and keep us posted on new ideas.Drew   "Fuses are only 10 cents...go for it."