525 header Y pipe reduction
 

I just took off headers and the Y pipe for the silent choice. Why does the inlet of the Y pipe reduce so much. The water passage on the top does not go into here it. It doesn't really seem like it needs to be there and am thinking about cutting it out from the inside. It reduces it to about 23/4". Any thoughts of why they do this?

I think what Speed is trying to say here is that the tail pipe that clamps to the header has a cone shaped reducer welded in by the flange that is necked down to 2 3/4in. Then after that, the y pipe has a hole cut into it so some of the exhaust can go out the prop. The boat doesn't have captains call? What up with that?

Why does that matter? About the only time you should run silent choice is off plane.

Well the 2 3/4 thing is more puzzling to me. 4'' pipe reduced down? Just wondering why. The exhaust going threw the prop on a noise maker seems kinda funny to me also.

As stated, only use the quiet mode at idle on a 525. I have Q&Q also. The inner sleeve is to stop reversion. DO NOT cut them out or modify them!

ok TCH I can see why they are there now that you pointed that out. I do not have a true captains call on my exhaust there is no switch or diverter in them so running it through the prop at any time is not an option for me. I have read that it is not good to run silent at higher RPM though. Thanks for the info