genIV lsx based exhaust
#1
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Joined: May 2007
Posts: 292
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From: Stuart, fl
looking for a set of exhaust manifolds and risers for a lsx based motor that has o2 provisions or that can use the dana riser spacers that have o2 bungs
are they any out there??
i know about the crusader ones but the risers are specific and do not use the same pattern as regular risers that i can use the spacer with o2 bung?
thanks
are they any out there??
i know about the crusader ones but the risers are specific and do not use the same pattern as regular risers that i can use the spacer with o2 bung?
thanks
#2
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Joined: Jul 2005
Posts: 202
Likes: 2
From: Cedar Creek, TX
Good Luck... I do not think any of the companies utilizing LS based motors are going to offer manifolds that will work with Merc style spacers. Indmar also offers LS based motors but there manifolds are completely different. Plus most of the stock stuff coming out these days has to use cats which require a different exhaust manifold. CMI does offer some headers for the LS based marine motors. In fact Mast Motorsports offers a marine LS based motor with a set of CMI headers that APPEAR to have O2 bung located in the top of the collector.
#3
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Joined: Jun 2010
Posts: 1,119
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From: Central IL / Green Bay, WI
Nice that CMI is finally offering something. A couple years back when I was building my LSx Jet Boat, CMI, Stainless Marine, Dana, etc...nobody wanted anything to do with making some LSx marine exhaust.
#4
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Joined: May 2007
Posts: 292
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From: Stuart, fl
im trying to use a manifold for right now, rather than spend 8k in headers for the pair, would like to get the motors in the boat and just use manifolds while i work out the harneses ect then when i build the motors ill get some headers, maybe i can have a set of custom risers made for them
Last edited by b18cls1; 07-27-2011 at 08:45 PM.
#7
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Joined: Jun 2010
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From: Central IL / Green Bay, WI
I know, because i've done it.
At first glance, they look like they might line up ok, but they really don't. Here are the 351W manifolds I used....they required drilling the heads, and welding the manifolds to close a gap between the head and the manifold.



I was eventually able to make them work, but there is only one stud per primary holding them on to the heads. It is certainly not a drill one hole and bolt them on affair.
#8
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Joined: Mar 2008
Posts: 1,181
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From: Vancouver BC
There are a few cast manifolds out there. Kodiak and Marine Power are a couple. They have a dry joint between the manifold and riser so it's very easy to add an adapter, it'll cost you $40-$50 to have an O2 spacer machined. I've got hard anodized ones I sell for the Kodiak manifolds -$60.
#9
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Joined: Sep 2008
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False.
I know, because i've done it.
At first glance, they look like they might line up ok, but they really don't. Here are the 351W manifolds I used....they required drilling the heads, and welding the manifolds to close a gap between the head and the manifold.



I was eventually able to make them work, but there is only one stud per primary holding them on to the heads. It is certainly not a drill one hole and bolt them on affair.
I know, because i've done it.
At first glance, they look like they might line up ok, but they really don't. Here are the 351W manifolds I used....they required drilling the heads, and welding the manifolds to close a gap between the head and the manifold.



I was eventually able to make them work, but there is only one stud per primary holding them on to the heads. It is certainly not a drill one hole and bolt them on affair.
Steve



