FACTORY PIPE / CHAMBER

[Chris V]

Hello my engine builder recommends putting a 2.5 jet in the cooling line going to chamber. i assume to limit the water. has anyone done this before or used a jet works flow valve instead? pros/cons/inputs?

 

[Vumad]

Hello my engine builder recommends putting a 2.5 jet in the cooling line going to chamber. i assume to limit the water. has anyone done this before or used a jet works flow valve instead? pros/cons/inputs?

It's a budget mod. Use a old junk jet for free instead of a $55 flow control valve. Serves a similar purpose to dry out the waterbox. The advantage of the flow control valve is that is can completely shut off the water at idle and be fully open at WOT. I have a 3rd pisser that wyes off my stinger so I can see what my flow control valve is doing. It doesn't even allow water to flow until about 2500 rpm. Just for the record, that 3rd pisser annoys the bajesus out of me, but the boat runs good so I deal.

Personally, I prefer to go with what the guy who I am paying to tune my boat says over what the internet says. I've gotten plenty of bad advice and at least one stuck piston from the internet.

 

[Chris V]

thank you for the tech input. i do like the idea of the flow control. do keep water out at idle, so I'm assuming your pisser is after the flow control. i could see how that could be annoying because the water flow will come and go depending on rpm. however can be tuned my easily?

 

[Fro Diesel]

Or, you could just test your flow control valve with the ski strapped to the trailer while looking at the tach. No need to be adjusting it all the time.

To th OP: i run a restrictor in the cooling line after the headpipe, before the stinger. This increases pressure in the headpipe and leads to a better spray pattern. I have a handful of different restrictors i use depending on water temp, little plastic bushings from hardware store.