Alright, my dad has 4 Rockford PWR-410's in his Impala SS, and I have a 18 inch SS Rl-p that I just got. I know that the 10's get low, and that's what I want, but the Rl-p gets just as low, I think 4 10's have around the same cone area as 1 18, or around there. I know someone around here has used some of these, they're only from 1994 haha but they were top of the line back then, and they've been babied (Sp?) since then and are in perfect condition. The only reason I'm considering this is for space, it's hard to fit a 18 into a '87 firebird without taking the back seat out and using that space. The 4 10's I could fit a box into the back well withi some added on. The 10's have been IB for a lond time using the Impala's trunk, but we put the 10's into a 6cube box and they got loud as hell haha so I know being loud wont be a problem for either woofers, but which one would have more potential.
If you haven't ever seen the woofers, here's a link to a
ebay listing but it's in a different language haha
http://cgi.ebay.at/Rockford-Fosgate-RFD-1215-15HX2-2-mal-PWR410-gratis_W0QQitemZ290125166918QQihZ019QQcategoryZ57293QQcmdZViewItem
And here are the specs on the Fosgates, (PDF)
http://www.rockfordfosgate.com/scripts/rightnow.cfg/php.exe/enduser/fattach_get.php?p_sid=JMhtx7Fi&p_tbl=9&p_id=391&p_created=1084383055
