I've search many times but haven't really found an answer I'm looking for so forgive me but I would like to know if you remove the silent choice and cap or remove the "Y" pipe will it make the thru hull louder? I have a 454 and it does not seem to be loud enough when exhaust is "open" through the tips. I do not have mufflers and my tips are the slant cut with internal flappers.. the flappers work and if you open them by hand when boat is off and use a flashlight you can see through the diverters to the manifolds so I know there are no mufflers. my boat just does not seem as loud as it should be or like I want it to be compared to others like it that friends have. It is only the base 454 mcm non mag carb motor so will it even get any louder it I make it strictly thru hull? I know that some still goes out the prop but I don't think enough to make a noise difference right? Should I remove it and make it straight through or suck it up and build a real motor and get good aftermarket manifolds?

Also would a set of gills or some stainless marine manifolds make more volume than my stock cast ones or am I still dreaming and need to just build a dam motor??

thanks for reading my book report

Put a supercharger on it it will sound much better,
if you can see the manifold then it must be a straight through exhaust

Simple solution
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It will get a bit louder.

Different hulls with the same motor don't always sound the same. An integrated swim platform for example changes things. A few boats ago, I had a 454 MAG MPI w/silent choice. I repowered with a 496HO and removed the silent choice, including the Y pipe and I can't say I really noticed a difference. My next boat had a 525efi with CMI's and I still don't think I noticed a huge volume difference.

You didn't mention what boat you have but I will say this, If you are going to have the BARK, make sure you have some BITE! If your top speed is 50 MPH, you don't need to be making a bunch of noise.

Removing the silent choice will have negligible or no affect on the sound level of your exhaust. When open, it doesn't bleed off enough exhaust to make a difference. You don't mention what the boat is and other factors could be involved in terms of baffling the sound, ie: swim platform, proximity to water line, etc. If you decide to remove the silent choice, I would recommend pulling the motor and completely removing the y-pipe and capping off the exhaust properly with a block-off plate and gasket. You will get varying opinions on this, but IMO, you are better off not having an unsecured cast aluminum pipe just hanging there. Were it to break off, you will have a 3" water inlet wide open to the outside with no way to stop it. Having said that, I'm not sure it's worth doing at all if you're not going to add horsepower in the process.

thanks guys, ita a 96 baja 252. I realize I need a motor but I'm not ready to spend that kind of loot. its my first boat I don't know if I wanna dump money into it or upgrade in a couple years. I just wish it was as loud as my buddys 232 with a 454 mag mpi, I know his motor is going to be louder but his y had been deleted and hes running straight through with flat cut tips with external flappers, that's why I was wondering If I did this if it would make a difference. It does 58 all day long (56 GPS) and on a real good day ive seen 60 on the dream-o-meter but never checked it gps and I'm ok with that for now I just really want it to be louder. would it be worth it to delete the y (and yes I would do it the correct way and not just block off and leave it in place) or slapping a set of stainless or hardin seaward manifolds on for now until I build a motor? Or should I just suck it up and enjoy it for another year or 3 and get a outlaw or fountain....

I tired to post a pic but it said I had to have 10 posts first

IMO Just enjoy what you have. You are running basically a 4" open exhaust now (when open). Changing the exhaust will make no difference in loudness either by removing the silent or replacing with expensive aftermarket. The engine is what the engine is, if you want to "BARK" you need teeth. Nothing short of engine mods will affect that.
Good luck and enjoy what you have, Happy Boating.

the truth hurts, I was expecting this but I figured couldn't hurt to ask, I'm capable of doing heads and cam which would probably give me more volume and a nice lope to go with it but ive read that the MCM is not worth it with the cast internals so I know its not worth building this boat anchor. thanks for the advice Glenamy