Sihi Pump

[lmathews]

I was wondering if anyone is running a 3hp sihi pump with a gas motor?If yes how big does the gas motor need to be?Also using these pumps in a water cooling set up without putting it in a heated building how does it drain out so it will not freeze?I am thinking of purchasing one,but would like to see one set up with it hooked directly to a stream for the water supply.
Thanks for any info.