Differences in Marine Exhaust?

[waterboy222]

Trying to educate myself on different exhaust options.

What are the big differences between tube style headers, manifolds, dry pipes and rewarder-style headers?

From what I can tell, if you went above the rubrail and cut holes in the swim platform area, you could use a much less expensive Rewarder style header instead of one that exits below the rubrail.

Am I missing something here?

[Griff]

Rewarders are for open engine compartment jet boats. They are water injected to cool them just a little.

All the performance headers and HP manifold exhaust is water jacketed. Its a pipe within a pipe and water circulates between them. In a wet system water mixes with the exhaust at some point. Usually just before going through teh transom. With a dry system, the water jacketed risers extend all the way through the transom. Water does not mix with the exhaust and is usually dumped through a separate hose that is connected near the end of the tails/risers.

[waterboy222]

am I correct in assuming that a dry pipe configuration will be substantially louder?

[Madpoodle]

Yup

[Perlmudder]

am I correct in assuming that a dry pipe configuration will be substantially louder?

thats a good thing!!

[Seafordguy]

thats a good thing!!

Not if you're following them

[waterboy222]

what kind of gains would i see with a 420 HP 454 stock merc with dry pipes?

[mosi]

You would probably gain about 3 more noise violation tickets a year.

[waterboy222]

luckily we dont have noise ordinance on our lake

[Griff]

what kind of gains would i see with a 420 HP 454 stock merc with dry pipes?

Over the same brand wet exhaust??????? None except the noise.

[drpete3]

I am guessing comparred to stock manifolds. Right?

[waterboy222]

yes, compared to stock

[Mac]

what kind of gains would i see with a 420 HP 454 stock merc with dry pipes?

you dont want dry pipes! Most people at GLOC would hate you, also grda does have some noise restrictions aroud marinas and after dark

[waterboy222]

Whatup Mac! Glad to see you wandered over here! I think most people at GLOC already hate me, at least the wives do.. haha.. I dont think the dry pipes will be what I get. I watched some youtube videos and theres a HUGE sound difference.. Pretty obnoxious, especially trying to back into a slip at 2:30 a.m. after a night at uglys or hookers.. pass..

[VetteLT193]

There is loud, then there is dry. Holy crap loud. so loud you can't really have a conversation on the boat. so loud your neighbors will hate you. so loud the people at the dock will clap after you shut the engine off.

The other issue with running dry pipes is the pipes have to line up perfect with the hull, which usually requires high dollar custom welding. With wet you'll have a rubber coupler that gives you some wiggle room.

All of the aftermarket systems seem to be wider than stock, and not many of them (maybe even none of them) line up perfectly with stock for some reason.

[jeff1000man]

Stay away from dry, and the jet boat style headers will brobably end up with either someone getting injured on your boat because they are very very hot.

I have some rebuilt GILS and tails that will go right back in the same holes you have if you are interested.

Manifolds are mine, but the tails are a friend of mine. They work fine with 420's.

[BDiggity]

so loud you can't really have a conversation on the boat. so loud your neighbors will hate you. so loud the people at the dock will clap after you shut the engine off.

yup, have had people clap at table rock when i shut down. but they all were day cruiser people.

[GRADS]

I have dry pipes on mine and I wouldn't have it any other way. I went from having mufflers to dry pipes and it was a huge difference noise wise and I also picked up a little more RPM to the point where I should probably go up a prop size. Yes we do get the people at the docks clapping when we shut it off and we do get some complaints when we boat in Tahoe but oh well, I like the sound. As far as the comment about the pipes getting hot, that is not true. They are water jacketed all the way to the tip. I can post some videos of the boat with the mufflers and with the dry pipes if you like so you can hear the difference.

[jeff1000man]

I have dry pipes on mine and I wouldn't have it any other way. I went from having mufflers to dry pipes and it was a huge difference noise wise and I also picked up a little more RPM to the point where I should probably go up a prop size. Yes we do get the people at the docks clapping when we shut it off and we do get some complaints when we boat in Tahoe but oh well, I like the sound. As far as the comment about the pipes getting hot, that is not true. They are water jacketed all the way to the tip. I can post some videos of the boat with the mufflers and with the dry pipes if you like so you can hear the difference.

I was talking about the jet boat headers. I am a big fan of drying the pipe out until just at the tip. I have allways plumbed GILs to have a water dump on them.

[Perlmudder]

I can post some videos of the boat with the mufflers and with the dry pipes if you like so you can hear the difference.

its winter! of course your should post vids!