I have black rubber external flaps on my exhaust. I was thinking of switching to an angle cut tip exhaust tip. Everybody keeps saying watch for "reversion"


Please help.
Thanks

The flaps help keep splashing water out of the exhaust pipes. Usually at slow speeds or when in nuetral.

reversion is when water reverses and come back into the motor through the exaust usually when you come off plane. the rubber flaps help prevent this as do the flappers in the pipe,

Hmmm, well, reversion is really when the water in your exhaust system ( in a wet exhaust system) is sucked back into the cylinder through the exhaust valve during valve overlap at idle. Valve overlap is when the exhaust valve and intake valve are open at the same time. The flapper at the end of the exhaust pipe doesnt have anything to do with it. It does help stop surges of water from getting in your engine when it is off or if it quits while you are running and that big surge of water comes rushing forward.

formula is correct except that just water from the exhaust wont come back unless there is an abundance of it hence coming back in from the exhaust through hulls

Do you then think that switching to the angle tip and thus loosing the external flapper would be OK??????

Sorry, but Formula is RIGHT! Unless you are running a strictly dry stack exhaust, there is always water in the pipe and "outside abundance" has little or nothing to do with REVERSION. Now, to the point; If you are changing to an angled style exhaust tip, I suggest that you purchase ones that include the internal flapper. Your situation will be as good or better than it is now. --- Jer

You can purchase angle tips with internal flappers, then you have no worries. The flaps will protect you from the potential water surge that you get when coming off plane too quickly. But as formula said, reversion is from excessive cam overlap, and the water exiting your engine getting sucked back into the exhaust at the point where the water mixes with the exhaust gases. Thats why they sell long risers, and dry pipe systems.

They are both right actually. Reversion is the act of water entering the clyinder through the exhuast valve during valve overlap. It does not matter how it got in the manifold to begin with it is still called reversion. There is always water in the pipes from the riser or elbow to the tips, there is not water in the risers unless it got there for one od a few reasons one of which is water coming in the piped and down the risers during a quick drop off plane or a wake hitting the transom. You need one form or another of flappers to protect against this but it doesn't matter if they are internal or external.

sound like internal flapper is the way to go.

Thanks