2nd gen explorers have tremendous potential. very little is published anywhere on how to make them loud. they are a unmapped area needing experimentation.crx's have been tested thoroughly many of times. there are only 3 people that have done thorough testing in explorers. (and of course they tend to keep quiet). as for walling explorers... the only successful one was a bassrace 149 system, but its goal wasnt to burp loud. explorers potential lies in its street boxes, not walls. there are many other vehicles that have been proven already to work well with walls.
exploders excel in street applications with larger amounts of cone area. taking a single 12 it is hard to break 150. while in other vehicles, it is easy. with more cone area (like 2 12's or 2 15's or 4 12's) they will get loud. in my explorer i found doubling cone area with the same power to each woofer yields about 4 db.
a note. the roof brace is a problem. anything over 152 db legal at the resonant frequency i would recommend reinforcing it. (of course look into your organizations rule book). from what i have been told, a broken roof brace will decrease your score up to 2 dbs.
burp explorers are very fun to play around with. most of the time my burp systems could always be wired to a stable ohm load and played daily. with 4 12's i can play music about 6 db quieter than my burp score. (take this is with 2 batteries and a stock alternator.)
i hope more people spend the time to make these things loud //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif