[Enclosure for DD Audio Sl 612 D2?]

Okey that helps me a lot. But should I run a 3 Inch wide

round port or 4 inch wide ? And at what lenght? 

[Enclosure for DD Audio Sl 612 D2?]

So should I build a 2.5 cf box eaven though factory recomends 1.7cf?  Can the woofer break if i make too large of an box? 

[Enclosure for DD Audio Sl 612 D2?]

regular sized woofer and box didn't fit in my previouse car. I have seat exeo 2.0tdi wagon with back seats of now.  But  the old box broke so I need to make a new one for it. and i don't have the money to by a regular sized woofer right now. I plan to make the new box form 25 mm thick mdf board

[Enclosure for DD Audio Sl 612 D2?]

I want to run it between 30-35Hz and it's 12 inch subwoofer

[Enclosure for DD Audio Sl 612 D2?]

So i have been trying to make my own ported/vented enclosure for my DD Audio 612 sl D2 woofer but I don't have prior experience in this. I have GAS PRO 1001.1 amplifier for it and I plan to run it at 1 ohms. So do eny of you know how large of an enclosure should I make for it and what sized and lenght port should I use? Is 50l enclosure and 3 inch wide and 20cm  long port too small?