Nate, now is the time to start adjusting your EQ settings and the amp. You'd be surprised at what a difference one little adjustment can make. If you want even more punch then turn up the gain on each speaker, but not too much (burnt speakers are no fun).
Also adjust your crosover point on the amp. I believe it sohuld be at 80 Hz but I remember getting better results by increasing it a little to 90-100 Hz.
Try that and if you get clipping then turn it down a bit and then try again
You want to get your subs to be able to play at full blast without any clipping/noise/distortion.
It takes a while to get EVERY adjustment right (my deck had like 4 different things I could adjust and then some).
Your neighbors will love you
You're only running 2 x 350w RMS to each speaker. If you were to run 2 x 400w RMS (what the speakers are rated at) you might get an extra decibel or two.
How is the electrical system doing?
I remember at full blast my whole dashboard and every light in the car would dim. I hope that cap helps out.
Roy: maybe you'll start driving your car once you get your springs (drive)