35fountain

I am trying to figure out and understand this reversion thing. I have been having an idle problem for a couple of years. If my exhaust pipes are on the loud position open the engines after 2-3 minutes of idling start to load up. IF i close the the pipes silent position( Merc silent choice) it idles fine No loading up. I can idle all day with no issues. Someone told me when they are opened i'm getting reversion..
So my question is.. Would reversion be worse with the exhaust in the open (free flowing) or closed position holding back exhaust and water forcing it through a y-pipe and down through the transom and drive?.
I have NO stains of any sort in my manifolds or risers, just plain soot color

Raylar

Please describe which engines you have and any modifications done to them or if custome built, some build specs. It does not sound like a reversion issue unless something is wrong with the exhaust switching and routing system. Loading up is usually an overfueling or ignition issue and not one of reversion.

Best Regards,
Ray @ Raylar

35fountain

Both engines are 509 cu 490 hp crank .. crane cams 539/559 lift 228/236 dur @050 114 lba air gap manifold nickerson 850 dp custom holley carbs, msd dist, msd blue box ignition, EMI thunder exhaust. short risers, merc silent choice..As i said if the exhaust in in quiet mode..it runs smooth at idle no load up..when i open the exhaust..you can start to hear the exhaust sound change like some cylinders are either loading up or ? water?. No signs of water on plugs and oil clean. Does opening the exhaust pipes (no back pressure) cause the fuel to flow faster into the cylinders causing this or could it be reversion without stains in the exhaust pipes.. I wanted to update my cams to new ones with Compcams 546/566 lift 234/244 dur @050 LBA 112. Saleman at Comp Cam says it won't revert...?? and if it does ?? I haven't bought them yet
You would think it would revert with the pipes in the closed position..holding back the water and exhaust.