going to try !!

[cosworth34677]

ok im going to try to make a hydraulic pump. i think im going to try to make a gear pump. i know the closer yo can make the edges the more power you'll make . besides this is there any thing that i need to know?
i'm going to use a 540 motor . and two gear. in a chunk of aluminum i need to draw the cut file for the router at work .

can i use 48 ptich gear or do they have to be 32 pitch or bigger? and do the gears have to be the same size? any ideas will help thanks.