I have a '97 Speedster that gets water in the floor while sitting still with people in it. I've replaced the scupper valve with a new fancy one, and it makes no difference. My theory is that the boat is simply too shallow for this system to work effectively. It seems to constantly take gulps of water up through the scupper valve, and the vertical drop from the floor to the valve to the water line is almost flat.
At a boat show this weekend, I noticed that a new model Speedster did not have a scupper valve. When I pull mine out of storage this Spring, I plan on modifying this system. I plan to (1) remove the scupper valve and put a solid rubber seal behind it, effectively sealing it up. Then I plan to disconnect the floor drain hose inside the engine compartment, letting any floor drainage water dump directly into the bilge where the pump can get it.
Has anyone tried this, or found a better solution?