my first car was a 1999 Ford laser sedan - nothing special about it really. 2x 15" subs few neons, DVD player.
2nd car: 1992 Nissan Pintara Sedan. Audio and Visual car.
for the 2008 dB Drag Australian Finals i ran 2x Kicker L7 15" subs. score of 150.4dB
After that i ran a single 18" Digital Designs sub
This is it next to a Pioneer 12" sub
I added a wall panel to help increase dB score with a bit of a light up design for the car club i was part of at the time.
In the boot lid i ran 2x 6" speakers, 2x 7" screens and a 15" TV
In the dash i had a JVC 7" DVD player and a 7" screen above the glove box.
In the doors i ran 2x 6" splits and a 7" screen.
In total: 57" worth of screens and some MAJOR bass.