Going to break up floor, install Sump Pump basin. Run Toliet drain straight into Pit underground. Plumbing from a sink at bar (not in picture) and Sink drain will drain into top of Basin lid. My question is, Can i run a 2 in pipe from pit pump to the 2 in existing drain in ceiling? DO i have to have pump pit into the 4in? we have existing pit on the opposite side of house where basement remodel is not taking place. If Anyone can help with info on what i Need to do, and maybe with dimensions for stubs on the plumbing rough in. The water lines will also tap into 1/2 lines in ceiling just above. Vent will go straight outside. OR DO I EXTEND THE 4in AND ELBOW A 2in OUT OF THE NEW 4in, BRING THAT ELBOW THEN OVER AND DOWN TO THE PIT?

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