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niceguy
04-26-2009, 12:54 PM
I know this sounds really dumb, but I have a friend who has some really nice jet boat headers that he will literally give to me.... I realize they will need a little creative fabbing to get them into my Sonic, but my question really lies in the cooling of them:

These use a small fitting in each of the primaries that injects a slight amount of water to cool them. He used these headers on a 540 with a huge mechanical roller in it and didnt have any issues with water being sucked in. He said after a run you could lay your hand on them and they were only marginally hot, but not enough to burn your hand.

Now having said all that it got me to thinking.... why can't I use these in my Sonic? I might have a total of 300-400 bucks in them after all the fab adjustments are made.

Does anyone have any direct knowledge of why this WILL or WILL NOT work?

Ratickle
04-26-2009, 02:06 PM
I know this sounds really dumb, but I have a friend who has some really nice jet boat headers that he will literally give to me.... I realize they will need a little creative fabbing to get them into my Sonic, but my question really lies in the cooling of them:

These use a small fitting in each of the primaries that injects a slight amount of water to cool them. He used these headers on a 540 with a huge mechanical roller in it and didnt have any issues with water being sucked in. He said after a run you could lay your hand on them and they were only marginally hot, but not enough to burn your hand.

Now having said all that it got me to thinking.... why can't I use these in my Sonic? I might have a total of 300-400 bucks in them after all the fab adjustments are made.

Does anyone have any direct knowledge of why this WILL or WILL NOT work?

They had to of been double wall, correct?

Chris
04-26-2009, 02:25 PM
If you remove the engine hatches and run them over the transom, you'd be OK. But they have to be water-jacketed to be in an enclosed engine compartment. If you get caught, you'd be fined and probably towed. If they burned your boat up, your insurance would likely tell you "too bad".

MOBILEMERCMAN
04-26-2009, 02:50 PM
They also have a whole near the injection point to allow the water out. I would say no go. You are asking for trouble.

2112
04-26-2009, 02:58 PM
I ran them for years in a hatch covered boat (and thru transom) but, I am a maintenance fanatic and kept them in prime operating condition at all times.

I sold the boat 10 years ago with the headers still functioning.

.

old377guy
04-26-2009, 03:06 PM
I ran them for years in a hatch covered boat (and thru transom) but, I am a maintenance fanatic and kept them in prime operating condition at all times.

I sold the boat 10 years ago with the headers still functioning.

.

yeah, but it's a known fact that it's ok with Ford motors..................................as they're so "cool"

Buoy
04-26-2009, 04:05 PM
I ran them for years in a hatch covered boat (and thru transom) but, I am a maintenance fanatic and kept them in prime operating condition at all times.

I sold the boat 10 years ago with the headers still functioning.

.

That was a badazz looking boat - kinda has an A-TEAM thing going on.
But it does look good.

Ratickle
04-26-2009, 08:12 PM
Okay, I've got to get this straight. I've owned two jet boats and the headers were still double wall.


You guys are telling me you can run headers which rise, and are not double wall, and inject water at the lower elbow into the header for cooling and silencing, and not have water reversion issues when the motor is idling?

Or have water run into the heads when the engine is shut off?

How?

MOBILEMERCMAN
04-26-2009, 08:21 PM
The older headers I have seen,and it has been a while, had a whole in the lowest part to allow the water to escape and not puddle

Ratickle
04-26-2009, 08:25 PM
The older headers I have seen,and it has been a while, had a whole in the lowest part to allow the water to escape and not puddle

So water was forced out under pressure when the engine was running?

MOBILEMERCMAN
04-26-2009, 08:39 PM
I am not a jet boat guy, but that is what I have seen when they are not jacketed.

niceguy
04-26-2009, 11:14 PM
I looked at the headers and it looks like the fitting is located at the lowest part of the bend (after it comes out of the head) and I was told it only sprays a fine mist until you rev the motor then it sprays more. So the water wont run into the ports as it would have to go uphill (crude description, but I cant think of any other) and the fitting is at the very bottom so it will drain back into the lines when the motor is off. I don't see how it doesnt pull water in the motor at idle, but I have actually been in the boat and the motor has run strong for several years now.... and it thumps pretty hard at an idle. SO I dunno?

Ok, so dare I ask if anyone has built their own headers? I ask cause if these wouldnt work, then I could try to double wall them... but jeez what a PITA. LOL

2112
04-27-2009, 12:53 AM
Okay, I've got to get this straight. I've owned two jet boats and the headers were still double wall.


You guys are telling me you can run headers which rise, and are not double wall, and inject water at the lower elbow into the header for cooling and silencing, and not have water reversion issues when the motor is idling?

Or have water run into the heads when the engine is shut off?

How?


There is a SS TEE valve (Basset) that only allows water into the primaries at a preset pressure/RPM I had mine set at about 1200rpm. Water running into the collectors just in front of the transom is always flowing keeping any rubber connector and fiberglass cool.

As Jim said, the primaries have weep holes at the lowest point in the primaries so any water that pools there will drip out. At speed, the holes have vacuum pulling air in. I made sure the cam lobe separation was 114 degrees and never had any reversion problems.

.

2112
04-27-2009, 12:56 AM
I looked at the headers and it looks like the fitting is located at the lowest part of the bend (after it comes out of the head) and I was told it only sprays a fine mist until you rev the motor then it sprays more. So the water wont run into the ports as it would have to go uphill (crude description, but I cant think of any other) and the fitting is at the very bottom so it will drain back into the lines when the motor is off. I don't see how it doesnt pull water in the motor at idle, but I have actually been in the boat and the motor has run strong for several years now.... and it thumps pretty hard at an idle. SO I dunno?

Ok, so dare I ask if anyone has built their own headers? I ask cause if these wouldnt work, then I could try to double wall them... but jeez what a PITA. LOL

Mine was developed by Drew Backlund (friend and mentor) of Drew Marine. (509) 535-3393

He ran them for years in his championship K-boats and in his 38 Scarab KV.

2112
04-27-2009, 12:57 AM
That was a badazz looking boat - kinda has an A-TEAM thing going on.
But it does look good.

Thanks! It was my first boat. I had it built in 1991 as a 92' model. It is a Warlock 24. Euro. Blue gelcoat with a red marine cloth interior. :sifone:

Ratickle
04-27-2009, 07:12 AM
There is a SS TEE valve (Basset) that only allows water into the primaries at a preset pressure/RPM I had mine set at about 1200rpm. Water running into the collectors just in front of the transom is always flowing keeping any rubber connector and fiberglass cool.

As Jim said, the primaries have weep holes at the lowest point in the primaries so any water that pools there will drip out. At speed, the holes have vacuum pulling air in. I made sure the cam lobe separation was 114 degrees and never had any reversion problems.

.

Wow, thanks for the info.

tim brown
05-06-2009, 01:49 PM
I ran a set on a force 220 Baja for a while with a ZZZ 350 small block . you need to wrap the pipes with the white heat wrap and use the water shut off valve mentioned earlyer . do not put your hands on them , they will hurt verry much , trust me . Tim:26:

Chris
05-06-2009, 03:43 PM
Let me reiterate- you can do it, but you're on your own if you do. It is absolutely against Coast Guard equipment regulations. If your boat burns, your insurer is going to laugh at you. If someone gets hurt, you could have issues beyond financial. In a jet boat, the worst thing that will happen is that the tubes will turn blue if the valve doesn't work. In an enclosed engine compartment, the way you'll probably find out is when you see the smoke & flames.

It's a cheap way out of buying the right tool for the job.

sanger rat
05-11-2009, 04:00 PM
Most Jet-Vdrive guys with big cams are using a Banderlog valve to turn the water on and off. http://www.banderlog.com/products/waterInjectionValve/waterInjection.html