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How to determine what exhaust I need?

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Old 07-24-2022 | 02:52 PM
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Default How to determine what exhaust I need?

There are so many exhaust options, how do I determine what exhaust I’m going to need?Custom 496 stroker motor puts out 570 hp 670 foot pounds of torque. I’m going to be redoing the air inlet and put a through transom exhaust with a captain‘s call switch to route the exhaust out into the water if it’s too loud.

Replacing my 7.4l it currently uses a wet exhaust system. Id prefer a wet system to keep the manifolds cool.
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Old 07-24-2022 | 03:01 PM
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Stainless marine
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Old 07-24-2022 | 05:51 PM
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What cam?? Stainless marine is a great exhaust, What you will deal with more given healthy numbers from a 496 is the possibility of reversion, a captains call could possibly increases that risk it really depends on the build of the motor. If your motor designer/builder is a good marine guy he should be able to tell you.
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Old 07-24-2022 | 07:53 PM
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With those numbers I doubt you will be able to run silent choice. If you can swing it , gen3 stainless marine is hard to beat.
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Old 07-24-2022 | 08:07 PM
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Originally Posted by 302Sport
Stainless marine
yup, and ask to have the dam put in if not standard. This helps even more against reversion.
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Old 07-25-2022 | 09:42 AM
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Originally Posted by phragle
What cam?? Stainless marine is a great exhaust, What you will deal with more given healthy numbers from a 496 is the possibility of reversion, a captains call could possibly increases that risk it really depends on the build of the motor. If your motor designer/builder is a good marine guy he should be able to tell you.
Motor delivered today...

From the package...

. THE CAMSHAFT IS A NEW ELGIN INDUSTRIES E1143P AND WITH A TRUE CLOYES DOUBLE ROLLER CHAIN SET. THIS CAMSHAFT IS A HYDRAULIC LIFTER GRIND .576 LIFT 246 DURATION @.050 ON BOTH THE INTAKE AND EXHAUST AND IT IS GROUND ON 108 DEGREE LOBE SEPARATION

Sorry for the caps am using my phone,. I quickly and copied and pasted this from the description
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Old 07-25-2022 | 09:46 AM
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Smarter guys will chime in, but I think 108 will be a problem with wet exhaust
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Old 07-25-2022 | 09:48 AM
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Originally Posted by Batmeat
Motor delivered today...

From the package...

. THE CAMSHAFT IS A NEW ELGIN INDUSTRIES E1143P AND WITH A TRUE CLOYES DOUBLE ROLLER CHAIN SET. THIS CAMSHAFT IS A HYDRAULIC LIFTER GRIND .576 LIFT 246 DURATION @.050 ON BOTH THE INTAKE AND EXHAUST AND IT IS GROUND ON 108 DEGREE LOBE SEPARATION

Sorry for the caps am using my phone,. I quickly and copied and pasted this from the description
Dry exhaust with no water even crossing the exhaust stream at the end. Has to be watercooled in an I/O application.

This type exhaust legal for your area ?

Dimly lit minds like mine wanna know how this got delivered ? Was this ordered as a I/O marine engine of course.


Last edited by SB; 07-25-2022 at 09:50 AM.
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Old 07-25-2022 | 11:34 AM
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Originally Posted by SB
Dry exhaust with no water even crossing the exhaust stream at the end. Has to be watercooled in an I/O application.

This type exhaust legal for your area ?

Dimly lit minds like mine wanna know how this got delivered ? Was this ordered as a I/O marine engine of course.
i live and boat in Wyoming. We have no exhaust laws for boats.
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Old 07-25-2022 | 11:43 AM
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We run dry exhaust. Stainless marine.

it has been confirmed by dockhands at our local watering hole…we are the second loudest boat in the area.
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