Wiring for 2 subs for max performance

Go online and find out what the lowest stable olm rating your sub's run at and that your amp can run at. Then wire them to that and tune it .

Run your subs in stereo at 2 OHMS.

This amp is rated at 500 watts into a 4 ohm load bridged mono or 250 watts x 2 into 2 ohm load stereo. Do not go below that impedance in either case. The amp was meant to dissipate a certain amount of power, driving it to hard will lead to damage. Your speakers look like they are dual voice coils @ 4 ohms each. To get the max power while still saving your subs would be to parallel the voice coils on each woofer then run them in stereo with your amp. Stereo 2 ohm is 250 watts per speaker.