Homemade Selectable Exhaust for 5.7L

75TowerOfPower

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OK I am looking at a newer Crownline and would like to have the chance to run thru hull exhaust but don't want to pay the price for captains call. I can weld and fab just about anything. So I was thinking of making my own Y-pipe and a valve. I don't mind having to turn the valves myself. I know there will be some days that I will want to run thru hull and days where I don't.

I was thinking of getting some 3" exhaust tubing from a muffler shop and using it to make the Y-pipe and after welding it up I would have a buddy powder coat it for me so there would be no rust issues.

Now the hard part, making a valve that's close to air tight so there are any leaks. I could buy ECO's from a automotive company but that as well would cost a good chunk of change. I could do a connection that doesn't even use a turnable valve and just put a plate in a place where a 4 bolt flange would be that has a spacer in for thru hull.

Just trying to see if anyone has tried this before or knows of anyone who has done this as well.
 

Bondo

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Re: Homemade Selectable Exhaust for 5.7L

Ayuh,.... Good Luck with it,...

I don't see a positive outcome though...
 

75TowerOfPower

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Re: Homemade Selectable Exhaust for 5.7L

OK would the y-pipe be quieter than thru hull?

With a kid on the way and I don't think the wife would want to hear V8 power all day I need something switchable or in between.
 

Bondo

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Re: Homemade Selectable Exhaust for 5.7L

OK would the y-pipe be quieter than thru hull?

Ayuh,... Through the Y-pipe, 'n prop hub, it's nearly Silent...

I put Thru-hulls on my last boat, 'n spent the next 10 years trying to quiet it down...
I won't make that Mistake again....
 

75TowerOfPower

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Re: Homemade Selectable Exhaust for 5.7L

I guess I should wait to actually own the boat before I get too far ahead of myself.

I know I can figure out a way to make it happen, was looking to see if anyone else was as cheap as I am.
 

HT32BSX115

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10,083
Re: Homemade Selectable Exhaust for 5.7L

OK would the y-pipe be quieter than thru hull?
You're kidding right?:confused::confused:

I had Capts Call on my 211 Liberator when I had the OMG 460 installed.

EVERY TIME I switched it to thru-hull, EVERYBODY in the boat screamed at me to TURN IT OFF TURN IT OFF!!!!!:eek::eek:

Everybody hated it..........

Oh....and don't try to make your own y-pipe. Just get one from Ebay etc. They're aluminum and they fit. If you get one that doesn't have a Y-pipe, you'll have to remove the engine to install it.............get one with "normal" exhaust and go boating. Don't get a boat with thru-hull or you'll have a hard time getting your wife to even go in the boat!!!



So.....yeah. Y-pipe is quieter.
 

75TowerOfPower

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Re: Homemade Selectable Exhaust for 5.7L

Sorry i may not have the terminalogy correct with the y-pipe. What I mean is it allows both thru hull and thru prop exhaust at the same time. I wasn't sure if there would be any change in sound from the y-pipe to just thru hull.
 

emilsr

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Dec 16, 2010
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Re: Homemade Selectable Exhaust for 5.7L

Sorry i may not have the terminalogy correct with the y-pipe. What I mean is it allows both thru hull and thru prop exhaust at the same time. I wasn't sure if there would be any change in sound from the y-pipe to just thru hull.

Thru hull will definitely be louder than thru prop, but baffled or muffled tips can quiet it down some. Honestly, with stock power you'll gain little or nothing by going with a thru transom exhaust other than the sound.....some like it, some don't. Unless you just want the "hot rod" sound, I'd stick with thru prop exhaust.

What you're describing sounds like Corsa's Quick and Quiet II system. There are 2 Y pipes on the tail of each exhaust riser, and a "bullhorn" leading from the Y pipes down to the drive. We had this setup on our last boat. Current boat has the switchable setup (Quick and Quiet Plus)......thru transom and thru prop, or just thru prop. You can buy this setup for around $1,000 and install it yourself, so long as the bullhorn is there (and it should be for a thru prop exhaust).

With your fab skills, another option you might consider is turn downs. Exhaust goes thru the transom, then the pipe curves and goes down below the water line. In this case you have quiet exhaust at idle, then the V-8 roar once you get on plane, with no moving parts to break. Gibson makes them if you want to do a google search, but you may be able to fashion your own out of some 4" stainless pipe.
 

Bondo

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Re: Homemade Selectable Exhaust for 5.7L

Sorry i may not have the terminalogy correct with the y-pipe. What I mean is it allows both thru hull and thru prop exhaust at the same time. I wasn't sure if there would be any change in sound from the y-pipe to just thru hull.

Ayuh,... I think so too...

While those things do in fact look like a "Y",...
Those are the Diverters...
With 'em set to Thru-hull, they allows the exhaust straight out the back, 'n it's LOUD...
With 'em diverted down through the Y-pipe, the exhaust is channeled down through the prop,...
It's Quite...
The Y-pipe is what's being called a "bullhorn"...

I don't have diverters,... Just 4" pipes, straight out the back...
They started as short angle cut nipples...
This is attemp # 10 or so to Quite it down...
f11297.jpg


It's Dead Silent at idle/ displacement speeds,...
But she really rumbles on plane...
 

Tail_Gunner

Admiral
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Jan 13, 2006
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6,237
Re: Homemade Selectable Exhaust for 5.7L

Ayuh,... I think so too...

While those things do in fact look like a "Y",...
Those are the Diverters...
With 'em set to Thru-hull, they allows the exhaust straight out the back, 'n it's LOUD...
With 'em diverted down through the Y-pipe, the exhaust is channeled down through the prop,...
It's Quite...
The Y-pipe is what's being called a "bullhorn"...

I don't have diverters,... Just 4" pipes, straight out the back...
They started as shThis is attemp ort angle cut nipples...
# 10 or so to Quite it down...
f11297.jpg


It's Dead Silent at idle/ displacement speeds,...
But she really rumbles on plane...



don't have diverters,... Just 4" pipes, straight out the back...
They started as shThis is attemp ort angle cut nipples...
# 10 or so to Quite it down...:D:D

Just plug the old holes ....I believe Bond-o you have the ability to do what ever you choose...;)
 

Speakrdude

Ensign
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Feb 25, 2004
Messages
942
Re: Homemade Selectable Exhaust for 5.7L

By-the-way, powered coating steel Does Not make it rust proof, by a long shot.
 

Bondo

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Re: Homemade Selectable Exhaust for 5.7L

Just plug the old holes ....I believe Bond-o you have the ability to do what ever you choose...;)

Ayuh,... No doubt, but I sold the Y-pipe, Years ago...
This spring I'm fixin' it nice, 'n proper....

I'm Selling the whole barge....;)
 
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