I've done some DB drag Racing in the past. It was fun, in an unconventional vehicle. Best I did was 134db off the glass on a Brüel & Kjær spl meter, with 3 JL 12w6's. Back then, the classes were determined by cone sizing/speaker volume. I'd often go up against hardcore guys with full blown pro systems. Never did it for the medals or trophies, just to know something I built had the ability to compete with shop built systems.
I'm in the Land Rover. I'll see if I can find some pics of the system. I know I have video stills of it.