Boat Tech

Keep on testing the engine just to be safe, But I will say the imco guys really know their stuff by trial and eare. They do LOTS of testing and inpesecting after almost if not every time they run a boat any where they go. They do put in 110% into all their stuff and work they do to try to get it right. Thay are one big that know what they are doing when it comes to boating.

jeff32

my experience is most of the time, everyone is right! the engine builder is right and is 100% sure he is not the cause of the problem. Then if there is a problem, the machine shop (if not done by the engine builder himself) says he did it right, it's the engine builder's fault, the your example, the exhaust guy that says something that may put the engine builder in problem... it's never someone's fault, but there is often a problem that needs to be solved...

Since 4 or 5 years, I go to a one stop shop, that does everything in house, EVEN drop the engine in and hook it up so if there is something not working, IT'S HIS FAULT!!!!

PatriYacht

Early HP500's had reversion problems with a cam smaller than yours and with risers of a similar length.

cloudmaster_321

So what's the solution if i don't have the hatch room to put on 3 inch risers? Eliminate the silent choice and go with mufflers straight out the back?

PatriYacht

Hate to say it. All of this stuff costs so much. Rule out leaks or cracks everywhere else first.

cloudmaster_321

That would be too bad if i had to get rid of the silent choice, i like having the option. There is a noticeable power increase going from silent to straight out as well.

Boat Tech

Having just mufflers is not that bad anymore, Or you could try to modify the engine hatch or have a new one to fit made. A lot of guys have had to do that before. Just my 02 worth. Good luck with it.

Sledge Hammer

Doesn't reversion show up on cylinders 7&8 first? He indicated he was seeing it out of 3&5. I also thought reversion would manifest itself on both sides to the same degree. He indicated one side did not have the problem. I had the same cam on a 468 I ran for 5 seasons with Eddie Marine exhaust and captains choice with no reversion problems. I would not think Imco would be more prone to reversion. Have you checked the head gasket?

cloudmaster_321

Well, the consensus is they are loosing the captains call, going with risers that exit the water further back becuase i can't get any bit of a riser height in there. Sounds like they are exploring options for mufflers and are mostly looking at IMCO's mufflers. They seem really high priced. I was looking at CP Performances mufflers, they have Hardin switchable mufflers, as well as some sort of exhuast muffler tip for the 496 motors to make them compliant with the regulations. Any thoughts on those or the switcheables? Seems like spending 900+ bucks on IMCO gatlins or someting of the sort is overboard.

cloudmaster_321

Your riser height may have been taller. I pretty much do not have any riser height currently, as well as the mixing not too far back. My eliminator eagle does not have a very tall deck, so no room for huge risers to make the captains call work.