Just tested the boat today. Idle around 1000 rpm, I got between 92 and 95 decibels roughly 3 feet away and 3 feet high from the silent thunder platform. Engine are 454-485 HP.

Still Not low enough to run on Lake Georges! Maybe I could be closer to 90 decibel with a idle of 750-800...

Do you stilll have the Silent Thunder box under the platform??
Or are you trying to get away without it

Jeff , Come down to the Hudson River for a ride . Don,t need mufflers yet. I would like to show you the lower Manhattan area. Or leave the boat home and ride with me and the wife. I to am thinking mufflers for next year. But don't want to lose any ponies from them with the newer boats getting faster with less hp.Can you beleave a 35 Lighting with 525's at 103 . Chit thats fast.

Silent thunder is on it. I just thought I'd be under 90, because when I compare with other that only has muffler that are under 90, mine sound/feels way more silent then mufflers...

And I still don't see how I could use muffler added to the silent thunder platform ???

I'd be glad to bring my boat there with a guide like you. I keep this in mind for next summer! Thanks for your invitation! I appreciate it.
As far as muffler goes, we are not in a bad position here in quebec generally speaking, but it not too far down the road, like anywhere else!

Anyboby here on that board added muffler on a silent thunder platform ???

If you have twin engines, does your state allow them to test with only one motor running? In Ohio, I've been told to have the ODNR test only one at a time for better noise compliance......................

another good point! But I think they must try to catch us up on 2 engines! More chances to make money giving tickets! But I'll try to find this info!

There is NO sound level testing ordinances in Canada, just a muffler law. Your silent thunder unit counts as a muffler, you are perfectly legal in Canada.

good to know! I just hope it is 100% true for all province!