yet another scupper question

[oldfielder]

Ok-So with my stern heavy i/o I've pretty much ascertained that going out the transom will require my scuppers to be below the water line or right at it. I think this pretty much rules out the ping pong balls.
So here's the question: If I have scuppers below the line will they drain fine if I just use thru-hulls with flaps like the gemlux. I'm happy with the floor drains for most applications, but every once in a while I have the nightmare vision of taking one over the bow in montauk and needing that h2o out of there fast. I've seen all kinds of thru-hulls below the waterline and I assume some of them are drains.
I know this also adds another element of gate valve or seacock into the equation-I'm really just wondering about the drainage factor.

[Blackfin26]

A friend of mine just showed me a set of flapper scuppers from Australia that are spring activated and seal water tight. I've also seen people use a pvc/round type scupper and clamp a piece of 8-10" rubber tube to the outside. The tube stops water from backing up the scupper.

[abl1111]

I'd like to add to this - I don't like the size of the floor scuppers - they are TINY for a 23' ocean going boat.

I would like to enlarge the hole and use an undetermined (1) way valve idea. Currently, I use the Vortex ( brilliant idea ) - the best mousetrap I've seen without lifting the floor which I am NOT up for. Unfortunately, a Vortex would not work with a bigger hole

I am surprised there is no other fix; DIY, or that $ could buy...

[oldfielder]

I really have no worries when I fish the sound, which is my primary use for this boat-Some of those standing waves in the rips in montauk can get a little unpredictable-espec. on moon tides and I'm just thinking out loud here. I guess it's really just a question of whether I want two more holes below waterline and
whether they will drain well down below the waterline. Capt. Chuck has the ones I want, but his are above the waterline.
I just can't imagine draining any significant water through the current design.

[Squido]

I am doing the same thing. I have a 1979 23' and my scuppers are striaght out the back as well. I am going with 1 " Seafit Brass valves and hard pipe right out the back. They used to have big loops to them but that is no good. My pipes used to be 3/4" but now I will have 1 "

[RWatts23]

I installed 1 1/4" at the water line, I dont have any flappers or any thing like that, you can see them in some of the pics of the boat in the water (for sale thread) I did raise the deck so this may not work for some of you. I dont have any issues with water on the deck. If a large wave, or backing down does bring in some water, it stays in the deeper channels made by raising the deck.