I have posted before but I think I should introduce myself since I think I'll be sticking around.  You guys seems to know what's up and it's always good to hear as many peoples opinions as possible. My name is Zach Halverson.     I just bought myself a couple rl-p 15's after searching around, passing on RE, done waiting on Adire, and not finding one bad review on these subs.  I've got a big project going with my 2001 Jeep Cherokee, upgrading my system big time. The question I currently have is how to best mount these things.  Currently I have designed a box with 3 ft^3 each tuned to 28 hz.  The slot port is 2.5x14 to give 35 in^2 of port area and have about 35 inches of port length.  The port takes a 180 degree bend and I was wondering how big of a deal that is?  Currently I have it where the sub and port are up-firing.  I have been reading and many people suggest an up-firing sub and rear-firing port for SUV's?  Do you guys agree?  If I went this way, would you want the port at the top or bottom of the box?  Oh yeah, due to the size constraints I can't really just turn them around and see what's best.  The amp that will be running these is the crossfire vr1000d which will be pushing about 600-650 watts rms to each sub. Sorry for all the questions right away but I want to do this right the first time.  I appreciate the help and it's good to be here!