Finally got most of my reversion stopped,still have water collecting in my tailpipes too much to install an O2 sensor.This is after having a new set of tubular manifolds made up and with dumps all he way at the end on the outside of the transom just before the flappers.I can still see the water being sucked up to the end of the individual pipes at the collectors so far nothing at the ports.I was told the boat was going to be much louder with the dumps at the end and it is...Has anyone used Gibsons transom mount silencers and if so I'm told any silencer can contribute to reversion but what about these flow thru designs.Secondly they are so ugly and long 13.5" does anyone make a shorter flow thru that will work as well ( know I want everthing but you know how it is) Need to be able to handle 600hp with a 4" inlet.Any insite would be helpful.