Always wanted to do this. Loudest I've had throught my 15 or so years playin around got me a 143.3 or something like that with a pair of 15's in a ford truck. I want 10 more db's, and im going to cut the shit out of this car until i get what i want for airspace. Its gonna be brutal, but thats okay i only paid $50 for it. This is literally day one shit..all i've done is pull out the back seat, break off the wood peice that "seals" the back of the seat brace from the trunk. Tons of measuring as well. If i have to also cut a big ass hole in the trunk..its going to happen even if it only gets me the 1.5 cubic feet extra that ive measured. haha. Looking at a 200 A alternator from irragi . Plan is either 3 15's, or 2 18's and 2500 rms. Kinetic batteries are in the plans. Going to be a slow build from nothing..so stay tuned if you are into that sort of thing.