You have to find out 3 things.

-What is the impedance of these woofers? Are they 4ohm...2ohm?
-Are these woofers dual voice coil or single?
-How are they currently wired together in the box?

All that will determine what kind of amp you will need. If I remember correctly, these are single voicecoil 4ohm subs. If so, chances are they are wired in parallel. You will need an amp that will put out enough wattage at 2ohms. Another thing is you will need to find out what the RMS wattage rating of the sub is...peak power doesnt tell us too much.