[rainmanspl]

True Aznboi. Donathion, I do not intend to disrespect, but as a seasoned competitor and former world champion builder I like to be helpful. I have built an enclosure for 4 8" that would consistently produce 153 - 155dB. This is below the window line in the cargo area measured legal "on the dash". This install would also score very well in SQ.
Too low of a tuning can and will negatively affect impedence rise. A 1000watt 1ohm amp isn't going to produce much @ 32+ohms. Dropping to even 6 subs and tuning somewhere between 40 - 46hz (maybe even 50hz) would improve your SPL score and lower your F3 to a comfortable point.
The four 8's were tuned at 44 or 45hz but would play below 25hz with no problem. Hey, your car looks cool. Nice work.