Is it ok if i face the subwoofer and port up instead on forward or backward in my trunk. 2010 altima.. would it make a difference?

Face it whichever way you want. It's your setup. It may make a difference on the meter, who knows what you will actually hear as a DD though. Try different positions and see what you want most.

it will still sound the same right?

I'll let you do it son

It may make your trunk rattle like crazy, maybe not.

As far as any difference, it may be louder, it may not. Test it out and report back

I am going to say facing the subs to the front sealed off or to the back would be your best bet, but try it and see.

If you face the sub and port forward into the cabin then you will lose some of the low end and you will have to seal it off the cabin from the trunk. To get the best sound usually, port and subs to the rear is a winner.

it will still sound the same right?

We don't know.

Try it and you tell us what you think

Is it ok if i face the subwoofer and port up instead on forward or backward in my trunk. 2010 altima.. would it make a difference?

might make your trunk rattle more and it might be louder you just got to play around with it

I faced it toward the back. It was my best option. It sounds great! and very loud as a first time system.