overheating amps?

Sounds to me like he parallel-wired two SVC 4 ohm subs, making it a 2 ohm load.  Then bridged this 2 ohm load across two channels, when the minimum load bridged should be no less than 4 ohms.  That puts a 1 ohm load onto each channel.

zoomie:  of course it hits harder when you put such a low load onto it.  But it's burning up.  You will find out what the Xplod in Xplod means.  Either wire one sub to each channel as suggested, or change the wiring from sub-to-sub to series, then bridge that.

This is a classic case where you should be using a mono amp to power two 4 ohm SVC subs.