I have fitted a shower tray using the drain provided which has a 40mm drain. The drain is not coping with the output of water from the shower head. If I fit a larger diameter pipe to the 40mm outlet, will this increase the volume of water being drained? - even though it will start by exiting through the 40mm pipe. I think my solution is either to reduce the output of water from the shower head with a restrictor or fit a different drain with a larger diameter outlet.