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Old 11-05-2025 | 06:33 AM
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Default Exhaust manifolds upgrade

I'm looking to upgrade the exhaust manifiolds on my 1998 Baja 24 Outlaw 454 for much better sound. Does anyone have experience with the Seaward Series Bravo Big Block Exhaust System 620-38035?
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Old 11-06-2025 | 12:36 PM
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My friend installed some last year on his 454 Mag MPI. It gave him some rpm so he is now hitting the rev limiter and needs to go to a higher pitch prop. And it did make the sound louder and deeper somewhat. Not like full headers but noticeable deeper tone.
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Old 11-06-2025 | 06:09 PM
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I had them on a 7.4L and transferred them to a 502 mag. Didn't notice that much of a sound difference if you have thru hull exhaust going from OEM to them.
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Old 11-06-2025 | 07:35 PM
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I have a pair of used CMI E tops. Stainless with Satin finish. Came off my Velocity VR1 when I had the engine rebuilt as a 540.
Here is a description.
Teague Custom Marine | CMI 454/502 E-TOP Headers - Satin Kit https://share.google/7hxL72r51XBelNnCj

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Old 11-07-2025 | 01:10 AM
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Is it strictly for sound? You won't notice a sound difference at all unless you get dry to the tip style headers, not from a manifold

That said, it's lighter and better corrosion resistance, so if you are replacing them anyway they are a good OEM replacement
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Old 11-07-2025 | 07:27 AM
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Thank you for the feedback
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Old 11-07-2025 | 07:35 AM
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Originally Posted by CheckmateScarab
Is it strictly for sound? You won't notice a sound difference at all unless you get dry to the tip style headers, not from a manifold

That said, it's lighter and better corrosion resistance, so if you are replacing them anyway they are a good OEM replacement
Yes I want sound, louder than stock. Thank you for the feedback.
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Old 11-07-2025 | 07:36 AM
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Originally Posted by xlint89
I had them on a 7.4L and transferred them to a 502 mag. Didn't notice that much of a sound difference if you have thru hull exhaust going from OEM to them.
Sounds like I need headers for louder than stock sound.
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Old 11-07-2025 | 07:37 AM
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Originally Posted by xlint89
I had them on a 7.4L and transferred them to a 502 mag. Didn't notice that much of a sound difference if you have thru hull exhaust going from OEM to them.
Thank you for the feedback. I need something for louder sound than stock.
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Old 11-07-2025 | 07:37 AM
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Originally Posted by 87MirageIntruder
My friend installed some last year on his 454 Mag MPI. It gave him some rpm so he is now hitting the rev limiter and needs to go to a higher pitch prop. And it did make the sound louder and deeper somewhat. Not like full headers but noticeable deeper tone.
Thank you for the feedback.
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