Cooling Water Jacketed Headers

[PC Rat]

My boat already had Lightning headers on it when I bought it, so I don't know if the headers came with a recommended way to plumb them. Does it matter whether the water pressure going to the headers has a regulator or bypass in the line?
Since my Aggressor pump has two water ports, I was thinking of using one to cool the engine (which has a pressure bypass in the system) and the other one solely for the headers. The cooling line for the headers will have a valve at the pump (just like the engine cooling) so I can somewhat meter the water volume.
So, it seems like the difference would be:
If the headers and engine were both run off the same system - as I went faster, I would get to the point where the water volume would stop increasing because the bypass would open.
If the headers were plumbed with no bypass - as I went faster, the water volume would keep increasing; or would I get to the point where the hoses would become a restriction?
Brian

[Danhercules]

Another question, do you want cold water going into your headers?

[SmokinLowriderSS]

I don't see the point of the complication, and just how cold are you wanting to run the header tubes, and why?
I'm not running any pressure bypass, all is controlled from the valve at the pump. I am plumbed to the engine front, out the t-stat cover, over to the header manifolds, and done with it from there. I have never had any block pressure/blown gasket or engine overheating problems, 28 years This is the first year for the headers, the logs lasted that long. My engine USED to run 135-140 WFO, idle about 170-180 and no trouble with condensation in the engine. It now runs 118 WFO and idles 156 (new dauges are digital), and I am going to close the inlet valve slightly this weekend to try to bring it up about 20deg.
All of my lines are 5/8" heater hose, except the 4 lines from the header manifold to the header tubes, those are 3/8", and 4 of them are far more flow area than a single 5/8" suply to them. Even after idling a while to a stop, my header tubes will not burn anyone, although you will not exactly lean on them all afternoon either. I do not worry about overpressuring the hoses as all the rubber is after the controll valve, which is threaded hard to the steel suply line from the pump.
At some point, the controll valve will wind up becoming the restriction on flow volume as increasing pressure gradually produces less increased flow thru the restriction. If you still have pressure problems that trigger the relief valve, I'd want to know why. Jacketed headers flow a lot of water volume, injecteds do not and require a less simple plumbing setup to maintain flow and controll pressure.
Just my $.02. Best of luck to ya.

[jeffroe]

i just went from bassett wet over the transom headers to the water jacketed headers and what a difference in exhaust note. using the same bypass valve i had on the overtransom header the jacketed headers are almost 1/2 as quiet but still bark w.o.t. not sure about the water volume question i guess the nice thing about the jacketed header is water can't go into the motor if there is to much volume so what can it hurt? try it :idea:

[1978 Rogers]

Don't you just plumb them the same as logs?

[jeffroe]

yes they have a rail type set-up w/drains.

[PC Rat]

I'm not trying to run more water, I just thought that if I ran cold water I wouldn't need as much water to keep the headers cool.
Smokin,
My water manifolds have 5/8" tubes for the individual hoses to connect to; how are your 3/8" hoses connected?

[SmokinLowriderSS]

I'm not trying to run more water, I just thought that if I ran cold water I wouldn't need as much water to keep the headers cool.
Smokin,
My water manifolds have 5/8" tubes for the individual hoses to connect to; how are your 3/8" hoses connected?
The front of the header manifold has a 5/8 nipple, aft of it are 4 ea, 3/8 nipples, in a line. 3/8 nipples on the bottom of the header tubes. The aft end of my header manifold has a 3/8 pipe plug in it too for draining in winter.

[SmokinLowriderSS]

Don't you just plumb them the same as logs?
Nope, backwards. Lake water to engine block first, out the t-stat cover, into the bottom of the headers, out the exhaust outlets. It's that simple.

[PC Rat]

Another question, do you want cold water going into your headers?
I was just looking at the Lightning site. They have an option for the water to go into the headers first.
From the site:
A common way to plumb Jet and V-Drive applications. The header is divided into two compartments. Water coming from the Jet Drive or water pump first enters the bottom of the header and flows through the main body of the header where it exits through a 3/4" female pipe fitting mounted on top of the collector. Next the water is routed into the front of the motor and out the thermostat housing and then back to the tail of the header where it enters another 3/4" female pipe fitting and mixes with the exhaust. A small weep hole is located between the two compartments that allows the collector to completely drain at shut down.

[wet77]

yes they have a rail type set-up w/drains.
Hey nice boat where do you run it?
I was thinking of a blower for my 540 Dart someday, what do you see for top speed?

[1978 Rogers]

Nope, backwards. Lake water to engine block first, out the t-stat cover, into the bottom of the headers, out the exhaust outlets. It's that simple.
Thats right. They only have an outlet. They don't pre-warm water line logs. my bad.

[flat broke]

I was just looking at the Lightning site. They have an option for the water to go into the headers first.
From the site:
A common way to plumb Jet and V-Drive applications. The header is divided into two compartments. Water coming from the Jet Drive or water pump first enters the bottom of the header and flows through the main body of the header where it exits through a 3/4" female pipe fitting mounted on top of the collector. Next the water is routed into the front of the motor and out the thermostat housing and then back to the tail of the header where it enters another 3/4" female pipe fitting and mixes with the exhaust. A small weep hole is located between the two compartments that allows the collector to completely drain at shut down.
"Stock" Lightnings do not come with the provision for this. That is something , much like many other options, that can be added to a custom set. You're pretty much beating a dead horse on this deal. Run em as described above by feeding the block, then the headers and you wont have any problems. Mine get warm, but I can hold my hand on them while their running for a good amount of time. The volume of water you run through the system is irrelvant unless you're worried about a pressure issue. But since there was no mention of a pressure gauge, a pressure reading etc. I'm guessing you don't have a problem in that department. If you do, don't mess with the headers, just use a regultor or bypass between the pump and the block.
Good luck with it,
Chris

[PC Rat]

"Stock" Lightnings do not come with the provision for this. That is something , much like many other options, that can be added to a custom set. You're pretty much beating a dead horse on this deal. Run em as described above by feeding the block, then the headers and you wont have any problems. Mine get warm, but I can hold my hand on them while their running for a good amount of time. The volume of water you run through the system is irrelvant unless you're worried about a pressure issue. But since there was no mention of a pressure gauge, a pressure reading etc. I'm guessing you don't have a problem in that department. If you do, don't mess with the headers, just use a regultor or bypass between the pump and the block.
Good luck with it,
Chris
I'm not running them this way, I was just trying to answer Danhercules and 1978 Rogers' questions.