I am trying to come up with a shape or design of a simple piston with holes that will allow fluid to flow in one direction better than the other. Very Simple shock design. I have tried tapered holes so as to speed up flow in one direction and it worked slightly but haven't quite found the design that gives me enough difference to do what I want. I am looking to cut flow to about 1/2 in one direction compared to the other. Or speed flow in one direction it doesn't matter. Any ideas ? Or at Least a direction to look towards? I've seen the tesla valve but it is much to large to use on something so small.