if you build boxes that allow the right movement of air for your sub yes they can sound better but bulding a ox for a 18 and slammin it n any old car/truck wont do. you have to think about where you want port to be , port up rear to the left right. etc..

Define good? Ive seen sa8's wreck name brand 12's. But imo its gotta be clean too, I did a build with 4 x morel caw 638's in a newer Lexus. Guy didnt want a sub box so i built baffles in each door. The car was all ready really sound deadened from the factory but adding good aftermarket stuff made a huge difference. I think speaker size is only relative to part of a builders ability to utilize said speakers/subs mechanics. Then you have to to find a quality Hu then an amp ect blah blah blah
wheres that link to the 17 gold horn tweeter clip when u need it?

thats wht i said lol

sony is loudest

kill yourself.

My 2 1200 watt max sony amps and two mtx terminators twelves make your ears bleed. Fi btls suck

mounted in an empty refrigerator box those would be loud as fuck.

Double and flush mount baffle would make that bad boy a good .5 inches thick!

LOL. $70 speakers wont even make the shittiest cars trunk rattle.. ill bet my 3 tens will make shut your junk down.

and id have to pull them out the closet from 3 yrs ago. LOL. ive got $5k in audio. sundwown amps. ill bet my beymas will drown out your bess. lol