496 Exhaust on a 502?

[pat@osp]

Anyone know if the stock Merc 496 exhaust manifolds will bolt up to and work on a '99 502 MPI? I've seen info online that says yes and some that says no. I have a pair of 502's in a 400ss Formula with silent choice that need new manifolds so I'm not looking for major HP increases just new manifolds. If they won't work I'll end up getting Stainless Marines or Imco's but it seems like I could save a pile of $ if they would work. If they do fit are there any specific versions to look for? This is a raw water cooled set up running in salt water that will be fresh water flushed on a Hydrohoist with the drives out of the water (won't pick up salt water) after each use.

Thanks, Pat

[Raylar]

Pat:
If you are the same gentleman who asked this question over on OSO, I already gave you the answers there to all your questions.

Regards,
Ray @ Raylar

[MarylandMark]

In the interest of enhancing SOS's tech department:


I did a search on this but got more questions than answers :) I have a pair of '99 502 MPI's with silent choise exhaust and the stock manifolds and risers need to be replaced. This is a raw water cooled set up being run in salt water that will be fresh water flushed after each use

-Can I use the 496 maniflds and risers?
-What kind of suprises can I expect................bolt holes, brackets, etc?
-Is there a specific version I should look for?
-I've seen reference to aluminum and cast iron versions. Will the aluminum live for 4 or 5 years in salt water if flushed?
-Do all 496 exhaust have a dry manifold to riser joint?
-Any line up problems with the silent choice?

Not looking for max HP gains......they are just stock engines in a sport cruiser..........and these 496 manifolds seem to be available at some decent prices. My other option is a set of Stainless Marine manifolds and risers but it seems like this route could save around $4000. Maybe to good to be true?

Thanks in advance for the help.

Thanks, Pat


Answers as follows:
question # 1. Yes
2. Some bracket modifications for oil
filter, hose connections, misc brackets
will be required but not major problem
3. All 2003 and later Merc 496 manifolds are
the same exclusive of alum 2003-2006
iron 2006-2009.
4. Using aluminum units in really good shape
with fresh flush after every use should not
be a problem.
5. YEP
6. Nope

Best Regards,
Ray @ Raylar

[pat@osp]

Pat:
If you are the same gentleman who asked this question over on OSO, I already gave you the answers there to all your questions.

Regards,
Ray @ Raylar

Ray,

I am the same guy. I haven't seen your response over there so I'll go check it out right now. I wasn't getting any responses over there so I figured I'd post on some other sites.

Thanks, Pat