That is what is bad about Bass Boost, it causes clipping if not used right. Check your gains. Yes, 800watts will make a huge difference, and maybe a bigger box.
so how do you use it right, and i cant get any bigger with a box, i have to take my weather stripping off to get the box in thats how tight it is, it takes 2 people and about 10 min to get it in! i took a lot time trying to desing this box