How much flow would this produce?

My tank is really loud especially where the water goes into the strainer to the sump. The strainer is part way out of the water because my mag 5 can't handle any more flow. I was wondering if I completely submerged the strainer with a little bit sticking up to prevent a siphon, how much flow would it be. It is a 1 1/2inch strainer plus pipe which gets reduced to 1 inch at the sump.