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Intro and two part question

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Old 04-07-2010 | 11:28 AM
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Hello everyone. I've been lurking on this board for quite some time learning lots of valuable info. My beast is nothing like a fountain, donzi, formula but I'm still looking to push some more power for cruising/fun. Here's my set up:

89 Maxum 2300 open bow
stock 7.4 bravo.

I'm replacing it with:
stroked 498
070 over flat top probe srs pistons
scat forged I beam rods
scat forged crank
bow tie aluminum heads
ultradyne hydr roller 601/601 @ 230*238* duration
Pretty much new block, heads, rotating, intake, carb, the rest will come off my current 454

Questions:
1. I just received a set of 496 take off aluminum manifolds with stainless risers. The risers have connecting water hoses in front and rear coming up from the manifolds. How do I set these up with current thermo assembly? Do I run the hose from thermo to riser and plug the manifold?

2. What is the benefit of Quick and Quiet II? I understand open thru hull and prop but does this lower the dc level due to open prop. I can't afford choice right now but I don't want to scream too loud so i'm thinking of some baffles/mufflers in the tips. Should I leave y pipe or go straight thru with silencers?

I currently boat what's left of Lake Mead. All opinions welcome.
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Old 04-07-2010 | 03:48 PM
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From: Between A Womans Leggs in IL
Default Fixx

Originally Posted by ramos45
Hello everyone. I've been lurking on this board for quite some time learning lots of valuable info. My beast is nothing like a fountain, donzi, formula but I'm still looking to push some more power for cruising/fun. Here's my set up:

89 Maxum 2300 open bow
stock 7.4 bravo.

I'm replacing it with:
stroked 498
070 over flat top probe srs pistons
scat forged I beam rods
scat forged crank
bow tie aluminum heads
ultradyne hydr roller 601/601 @ 230*238* duration
Pretty much new block, heads, rotating, intake, carb, the rest will come off my current 454

Questions:
1. I just received a set of 496 take off aluminum manifolds with stainless risers. The risers have connecting water hoses in front and rear coming up from the manifolds. How do I set these up with current thermo assembly? Do I run the hose from thermo to riser and plug the manifold?

2. What is the benefit of Quick and Quiet II? I understand open thru hull and prop but does this lower the dc level due to open prop. I can't afford choice right now but I don't want to scream too loud so i'm thinking of some baffles/mufflers in the tips. Should I leave y pipe or go straight thru with silencers?

I currently boat what's left of Lake Mead. All opinions welcome.
those manifolds need to be plumed like they are from the factory..
and don't take them apart,those gaskets are like 40-60 bucks a piece..
their should be a fitting on the bottom of the manifold, out from the thermostat housing to the fitting on the bottom of the manifold,if you have a 4 port housing you need to either get a y connector and connect 2 hoses in to one or replace the thermostat housing with this one..

http://cgi.ebay.com/ebaymotors/ws/eB...d=370319170134

whats the LSA on that cam..
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Old 04-07-2010 | 04:17 PM
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Here's the info on the cam:

284*/292*
230*/238*
112* LSA
108* ICL
.3533"/.3533" lobe
.601"/.601" valve w/1.7 rockers
The HR14 is the master lobe number for the intake
The HR15 is the master lobe number for the exhaust
The I/T 5266 is the serial number

The thermo housing in the link has the same # of hoses going to exhaust as stock. I'll just get a y connector for the riser hose.
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Old 04-07-2010 | 07:08 PM
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From: Between A Womans Leggs in IL
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Originally Posted by ramos45
Here's the info on the cam:

284*/292*
230*/238*
112* LSA
108* ICL
.3533"/.3533" lobe
.601"/.601" valve w/1.7 rockers
The HR14 is the master lobe number for the intake
The HR15 is the master lobe number for the exhaust
The I/T 5266 is the serial number

The thermo housing in the link has the same # of hoses going to exhaust as stock. I'll just get a y connector for the riser hose.
so your saying ou have a 4 port thermostat housing? the 2 front ports(starboard),the biggrt of the 2 goes to the circulation pump,smaller one (port side) goes to the sea pum. the rear 2 go to the bottom of the manifold..

is this what you have?
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Old 04-07-2010 | 07:55 PM
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No, 4 hoses leaving thermo housing. 2 hoses to bottom of manifolds and 2 hoses directly into the risers. Stock set up for 1989 7.4l 330hp.
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Old 04-07-2010 | 09:13 PM
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With those cam specs and stock 496HO exhaust, it is almost guaranteed that you will have water reversion.
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Old 04-07-2010 | 10:20 PM
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If reversion is an issue then I'll have to fab some extensions and have my machinist weld them on to the inner riser tube. How far should I make the extensions?
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Old 04-08-2010 | 10:53 AM
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What is the most practical application to fight reversion in my situation?

Should I weld and extenstion to the inner exhaust pipe so the water isn't introduced until the end?

Or, is it as simple as plugging the hose holes on the outside and inside bends of the riser along with one of the manifold's holes and run one hose from manifold and connect to end of exhaust?

I drew a pic showing both scenarios but I can't attach.
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Old 04-08-2010 | 11:18 AM
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For reversion. Buy the correct exhaust.
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Old 04-08-2010 | 12:06 PM
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Awesome answer to my question, I'm trying to find out how to combat reversion with 496ho manifolds. Any useful opinions appreciated.
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