what's loud enough?

I've been through many systems over the years from small cheap crap to some mid to high end stuff. I'm currently running a c1100.4 on 8 mids 2 supertweets with 1 15(on it's last leg with partial triple joint failure, likely from overpowering not clipping) that was strapped with apsms 1500s until one couldn't to the knockage. in the quest for more bass i've dropped alot of cash. my next plan is a 4th order wall in my backseat area with 5-8 10s or 12s either way they'll be the vvme subs, unless i find two vfl comps, hdc4s, or nightshades for the LOW LOW. This quest has inspired me to try and possible build this enclosure myself. Only one thing, i have no idea wth i'm doing. my design has been based off of meticulously thought out brain farts and ideas I've gotten from youtube. I'm not aiming for competition i just want it to sound good and be a low end monster. semi cyclone possibly any design ideas?

Here's a site that may help you if your gna diy....

http://windtunnelaudio.webs.com/contact-us

http://windtunnelaudio.webs.com/apps/photos/album?albumid=14458605

I think going to competitions will be very helpful because it might give you ideas to work off of. Also, there are people who have very detailed build logs that might also be of some help.

Thanks for the links. I try yo make it to comps when I'm off but I'm working most weekends.