Monaco20

How does it work?
What is the diffrence in sound level, compared with thrugh hull?
Does it gane or loose effect from the engine?

88242LS

Others will chime in here, of course there will be a differance if you take it off and stick pipes out the back, much louder, a few guys have cut a second set of holes to get more rumble, but still quiet in the harbor because at idle the holes are still underwater, I'm sure someone will post a pic so you see what I mean, and from what ive read over the years there is no performance gain with or without the platform.

masi242

Sorry, save your self the trouble it might sound a little better but no MPH diffrence.

tpenfield

Silent Thunder - the swim platform is the muffler for the engine. It has chambers inside of it and the exhaust comes out the exhaust ports. It is non-restrictive and sounds impressive at idle. It gives good noise suppression at cruising speed, without appreciable loss of hp. I think Silent Thunder is great.

I wish it were still offered on new boats.

mopower

I'm really surprized they don't , with noise restrictions becoming more stringent

ThirdBird

I'm surprised too. But, there were nasty rattle issues with the integrated platform Silent Thunder systems. Most people got so fed up with it they swapped to mufflers. I would think Formula could have easily beefed-up the system to get rid of the rattles.

It really was an innovative system. At idle and slow speeds, the exhaust/water had to push it's way under a set of baffles inside the system. When at speed on plane, the combination of forward motion and high exhaust output would basically blow the system free of any standing water. The exhaust just blew right under the baffles without any appreciable back pressure, yet still kept noise down. Pretty cool design.