7.4 headers
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7.4 headers

  1. #1
    Member MSCobalt220's Avatar
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    Default 7.4 headers

    Would this exhaust be worth putting on my boat, or should I go for tubular headers ? I have a 22" Cobalt bow rider with through transom exhaust using factory manifolds. I like the thought of tube headers for lighter weight and possibly a bigger kick in performance. I don't know anything about these SS manifolds. Here is a link.

    http://cgi.ebay.com/ebaymotors/stain...=p4506.c0.m245

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    They are very good manifolds, but..... unless you plan on building the motor, it won't do a thing for you. It may be worth 5-10hp in stock form, which will gain you nothing. On a high HP motor( 500-600) , it may be worth 30.


    Darrell.
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    28ft Sportcat
    With Twins

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    nice looking headers, but...IMO, not worth the price...u can find some nice headers (1/2 the price) on here in the Parts Spam section for a good price...u would be much better off ...just my .02 cents

    FastRat

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    Quote Originally Posted by FastRat View Post
    nice looking headers, but...IMO, not worth the price...u can find some nice headers (1/2 the price) on here in the Parts Spam section for a good price...u would be much better off ...just my .02 cents

    FastRat


    Fully water cooled, double walled headers for $500 ????? That would be a great deal. I'm pretty sure he has an enclosed engine compartment, so he has to have the watercooled units.



    Darrell.
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    28ft Sportcat
    With Twins

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    Quote Originally Posted by DMOORE View Post
    They are very good manifolds, but..... unless you plan on building the motor, it won't do a thing for you. It may be worth 5-10hp in stock form, which will gain you nothing. On a high HP motor( 500-600) , it may be worth 30.


    Darrell.
    Darrel, I am looking to do a top end change on the engine , looking for a 400 HP flattop 454 when I'm done . My boat has the 330 horse peanut port 7.4 . Mainly a set of large ovals and an intake manifold change. I like the double walled tube headers , but need to know if these would have as much of a torque increase as a good Lightning header ? And if they would support a higher Horse engine for future mods .
    Quote Originally Posted by DMOORE View Post
    Fully water cooled, double walled headers for $500 ????? That would be a great deal. I'm pretty sure he has an enclosed engine compartment, so he has to have the watercooled units.



    Darrell.
    Yup, enclosed engine compartment . $500 headers ? put me on 'em.

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    Look like improved factory manifolds rather than headers to me.

    You'll pick up far more with a cam/carb/intake/headers than with headers alone.

    I'm doing mine more for personal preference, I like the sound of Transom Exhaust. I am going with Lightning myself, they just look like real headers to me, and seem to be the best made/least expensive.

    EM

  9. #7
    cfm
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    Although I personally like the Lightnings better, the Stainless MArine manifold systems work extremely well in up to 600hp 502's and such. Inside those sheet type walls that you see, are individual stainless tubes. You can also rotate the pipes on the manifold which can help if the tails don't line up totally correct.

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    Thanks for the info cfm, I figured as much. Still like the look of the Lighnings better, like you

  11. #9
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    Quote Originally Posted by cfm View Post
    Although I personally like the Lightnings better, the Stainless MArine manifold systems work extremely well in up to 600hp 502's and such. Inside those sheet type walls that you see, are individual stainless tubes. You can also rotate the pipes on the manifold which can help if the tails don't line up totally correct.

    These are the second choice , I like the way they are designed . I want a set of Lightnings for the weight reduction part of the swap just as much as the performance gain . Waappp waaappp !!!

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