Replacing "log" manifolds with center risers?

[Danny_Ocean]

I have an older Mercruiser 330 (454) that has the "log" style manifolds. Raw-water cooling, no mufflers, through-the-hull wet exhaust.<br /><br />I would like to update to newer manifolds/headers. The boat will be used in saltwater after this season.<br /><br />Recommendations? What other parts need to be changed in this conversion?<br /><br />Thanks in advance,<br /><br />D. Ocean

 

[zzzzz]

Re: Replacing "log" manifolds with center risers?

Mercury now has ceramic coated manifolds and risers for your engine...not much more money for extra life in salt !

 

[yoced]

Re: Replacing "log" manifolds with center risers?

There are *lots* of options out there to replace the old log style manifolds. Take a close look at how much height you have to play with - now that your height is going to be near the center of the engine instead of near the back. Also look at how much distance you have to the exit at the transom. This will help in choosing the replacements.

 

[mercrewser]

Re: Replacing "log" manifolds with center risers?

If you want good replacements, buy direct from OSCO. They are the replacement manifolds that most of the suppliers use and you can cut out the middle man. Theyre in Souderton PA, right around the corner from me. Ceramic sounds better though and I'm not sure if they make those.

 

[zzzzz]

Re: Replacing "log" manifolds with center risers?

danny-you can get the merc ceramics at any marina that buys from LAND N SEA in pompano

 

[dmorley]

Re: Replacing "log" manifolds with center risers?

If you have the engine serial number you can go to the Mercury web page and e-mail them your question. At least when I did it they gave me a complete list of part numbers needed to convert from one piece manifolds to a manifold/riser set up. Be prepared to spend some money.

 

[Bondo]

Re: Replacing "log" manifolds with center risers?

The Big-block Chevy is the 2nd most Hot-Rodded motor in the World.... Right behind the Chevy Small-block......<br />EXCEPT, in Boats......<br />Then the Chevy Big-block IS the Most Hot-Roded motor, just Ahead of the Chevy Small-block......<br /><br />That said,<br />Your Options for Manifolds, Risers, or Headers is Almost Endless.........<br />Do a few Google searches.... You'll be reading for the next couple of Months.............