I looked up Pelton wheels but I need pressure and the way my stream is setup and it's real purpose which is to flow into rice like wetland patches I can't alter it. From where my wheel is located that is the only spot that has a vertical drop of around 4ft. Before and after this location I get a drop of a foot at about 80yards. I can't run a long pipe or the water will bypass the diversions where it feeds the patches.
Looks like most Pelton wheels need 10 to 20 ft of head to operate(powerpout.com). They call that low head but for me that hight means 1/2 a mile or more of pipe. Not an option for me. With 4ft of drop it seems my wheel can only be 4ft for an overshot. I'm maxed out on width so now the option your saying is to get more water over it to increase torque. Gonna give that a try.
Sucks that I have these limitations or I would go crazy with a hydro system that could produce some crazy watts.