dave i did this exact same build style last yr for the black civic with a 4 and tweet wrapped in alcantera suade, but we couldnt get the 4 to sound decent and it obstructed the driver veiw to much.. and it was a huge heat score for theft. i even had a 4 inch limo tint run across the bottom of the windsheild and it still was a theft issue... i have since removed them and hope yours do better for sq.....
i have no fear that this car will sound great....i believe its has the capability to sound better that the neon.....im guessing you had a midbass somewhere in the floor or doors?......what problems did you encounter with regards to the sq
ya i have an 8 inch in the door... i couldnt get the 4 to sound natural. just sounded very tinny, had it xover at 24/db from 250 to 700hz.... sounded like poo!!!! so i just gave up on her.... i think it was that the diamond audio 4 didnt like being in a sealed box that small. this time i am using different drivers in the a pillars and a different driver in the kick area and nothing in the door....
It is difficult to get small driver in a sealed enclosure that high to not sound 'tinny', pulled my share of hair out trying to tune that type of combo as well. You're right, the style of driver used makes so much of a difference...
Though, with that size of enclosure and vented, it should make life a little easier. I'm guessing that you may just have to try different port lengths and stuffing to find the best tuning for this particular vehicle/gear/seating position etc. Your 70Hz should be a good starting point. Also, with the sub in the dash as well... look out man, this car should rock.
Watch you don't get into any accidents from listening to a sweet sounding song track, lol!
flatish symetrical dash, my girlfriend has 2 kids, i need to be able to move product from store to store, its lowered 2" has 18" chrome wheels and all the windows are tinted and i dont mind the syling at all........its uber gangster