well you have two. 4 ohm subs rite? if you wire them in Parallel it will become a 2 ohm load with only one wire -right and left- but it depends i looked up your exact amp and when you bridge it. it goes to 400 to 4? (ohms) that would only work with one sub. so no you can bridge this. i would recommend buying a mono subwoofer amp and just wiring your subs in Parallel or series then u can use the full advantage to your amp. 2 channel subwoofer amps are not that necessary and are expensive. more expensive than mono. mono ar'nt made for one sub if you wire yours together. bottom line you cant. unless they were 2 ohm subs. not with this amp. this is your amp right ? http://signature.crutchfield.com/s_575P4002P/Rockford-Fosgate-Punch-P400-2.html?tp=35757
this amp is same brand 100$ less and more power it is mono you need to wire both of your 4 ohm subs in parallel and that makes it 2 ohm this amp gives 500w at 2 ohm.
if you dont know how to wire like that go here. http://www.the12volt.com/caraudio/boxcalcs.asp
hope this helps.