I'm afraid of my port being too long.i am by no means an expert but here is what I got... 1 team fi 18v2- 1 scv 4000 a couple of extra battery's 130 amp alt stock "mechman 270 soon" big 3-dual runs of 0 through out my box whic isnt built yet is 24t-24d-44w with a slot port 22.5x6" I'm wanting to tune to 28 for lows. I want it to be fairly loud but it's no big deal if it isn't I just don't want a boomy box tuned to 40 lol. Any way with a tuning of 28 and that size box I figured around 12 cubes before port-and with the port being 46 or so inches long I'll land near 8cubes after port. which puts me near 28 hearts or so... problem is with a port that long will I run into resonance problems if I set my crossover around 70-80 hz and is 135 square inches of port large enough thank you for any reply and constructive  criticism is welcome oh and also it's going in a 2009 Nissan Murano

Que?  Small box, low tuning = long port.

The rest of your question is really hard to read...

Sorry about that, I'm just worried that my port will be too long and I may introduce resonance from it being over 40" long 

Don't tune so low.  Past the range of diminishing returns.

you dont need a box tuned at 28hz for the lows, 30-34hz will be fine and allow you to play a range of music as well. I used to tune below 30hz but now its more around 30-32hz, just my personal preference.

Thanks a lot for the responses maby I'll tune a bit higher that will help with my port length. What about 135 square inches of port being enough? I will be running a scv 4000 on my sub, I know that I won't be getting 4000 watts out of it on the count of only having a 130 amp alt. Do you guys think that 135in is enough

Edited March 7, 20178 yr by Ernestgary

Should be enough . . And yes I would tune to at least 30 or so