Confused about water box regulator operation

[Rossterman]

Reading most posts, it seems that most explain that the water box regulator reduces water flow to the tuned pipe at higher speed/rpm. Something about less flow to allow,the engine to make more,HP and rpm. Looking at how the diaphram and needle valve work, the needle rises under higher pressure into the body as the diaphram fills which retracts the tapered needle and closes the hole in the bottom that feeds the muffler (on which it is mounted). That would mean more water flow is diverted at speed rather than less- exact opposite of what is commonly thought. Am I missing something?

 

[GGuillot]

Reading most posts, it seems that most explain that the water box regulator reduces water flow to the tuned pipe at higher speed/rpm. Something about less flow to allow,the engine to make more,HP and rpm. Looking at how the diaphram and needle valve work, the needle rises under higher pressure into the body as the diaphram fills which retracts the tapered needle and closes the hole in the bottom that feeds the muffler (on which it is mounted). That would mean more water flow is diverted at speed rather than less- exact opposite of what is commonly thought. Am I missing something?

Yes, you're overlooking that at high rpm the needle moves up to close off the water falling into the muffler. It's the exhaust flow, not water pressure that overcomes the spring pressure and pushes the needle to a closed position.

 

[etemplet]

Hmmmmmm.... after playing with the water Control valves on two GTXs I managed to convince myself that it was the pressure of the pump water that closed the valve and diverted "more" water to the muffler and less water to the pipe up front. This will be an interesting thread.

 

[Mekanix]

Water pressure.
At low rpm water is forced into the tuned pipe and exhaust can. At higher rpms and that means higher water pressure, the diaphragm will get filled with water and this overcomes the spring which closes off ththe water flow to the diaphragm and also the tubes pipe. But it will meter according to demand. As in it will not shut off water flow. It will reduce until the high pressure water equals the spring pressure. So there is lots of water flow when there is low water pressure and little water flow when there is high pressure.

The regulator regulates. It does not shut off the flow. It just reduces water flow to the pipe until it reaches a ballance.
However water entering the unit always goes into the exhaust can. But that is reduced to a very small jet so it doesn't rob the pressure you need to make the valve work. So the exhaust pressure through that little fitting is not more than the water pressure pushing back.

Hope that makes sense. It's my best theory.
Dont ask me how to tune the sucker's though lol

 

[GGuillot]

Water pressure.
At low rpm water is forced into the tuned pipe and exhaust can. At higher rpms and that means higher water pressure, the diaphragm will get filled with water and this overcomes the spring which closes off ththe water flow to the diaphragm and also the tubes pipe. But it will meter according to demand. As in it will not shut off water flow. It will reduce until the high pressure water equals the spring pressure. So there is lots of water flow when there is low water pressure and little water flow when there is high pressure.

The regulator regulates. It does not shut off the flow. It just reduces water flow to the pipe until it reaches a ballance.
However water entering the unit always goes into the exhaust can. But that is reduced to a very small jet so it doesn't rob the pressure you need to make the valve work. So the exhaust pressure through that little fitting is not more than the water pressure pushing back.

Hope that makes sense. It's my best theory.
Dont ask me how to tune the sucker's though lol

Ok, I'm learning, I was convinced exhaust pressure at 6K + is enough to force the pin up and overcome the spring, but it's actually water pressure.

 

[tobytd]

Turn adjuster in (increase spring pressure) - - more water in pipe - runs cooler - less RPM
Turn adjuster out (less spring pressure) - - less water in pipe - - runs hotter - - more RPM
Maybe not less water in pipe due to metered fitting but it slows flow at lower RPM

 

[Mekanix]

Thats why I say tuning is a mystery.
I've tried full in and out without any effect on performance. I have seen that some even have a washer under the spring as well as being full in.