Sub hook up question

I need to hook up two single 4 ohm subs bridged to a amp to get a four ohm load so i can get the max out of the amp. Can a do it through resistors or something like that.

No can do. You can wire them in series to get an 8 ohm load or wire them in parallel to get a 2 ohm load. While using resistors could drop the nominal impedance to a 4 ohm load, any additional power delivered by the amplifier would be lost/not delivered to each speaker. If your amplifier is only stable down to a 4 ohm mono load, you have only one safe option if you wish to run the amp in mono using two 4 ohm SVC subs ...wire them in series to get an 8 ohm load. https://www.the12volt.com/caraudio/woofer_configurations.asp?Q=2&I=41 ~wirewise~