Exhaust volume

[HenryOrlando]

Got a couple ideas, but has anyone had great success with reducing the engine and exhaust roar of the 8.1's...

[Chris Burkard]

Hi again Henry!

Tiara uses fiberglass horizontal mufflers on the Coronet. I believe they were manufactured by Vernea (sp?).

To replace those mufflers would likely require cutting the cockpit deck and then there is no guarantee that you could find another muffler capable of reducing the engine rumble that would fit.

Another avenue to follow would be add insulation to the engine room hatch and replace the engine room hatch seal. This may drop the decibel levels, but I'm not sure by how much. You could also look into wrapping the exhaust in the engine room with insulation blankets (I would consult with an exhaust expert before going down this avenue).

Sincerely,

[Pipgan]

I have a 2005 2900 w/ 8.1. recently measure dB at 82 at wot. My boat has sound insulation in the engine room.

[Chris Burkard]

Henry, Post a pic of your new paint job! If you give me permission, I can post it. It looks awesome!

[heygreg]

Inboard ski boats use FAE (Fresh Air Exhast) pipes. This is simply taking the exhaust and putting it into the water about 1 foot below to muffle the exhaust and sequester the CO.
Also, sound insulation is a must. Just remember, you are dealing with low frequency vibration (below 1000 hz) and thus the engineering should be based on absorption, not deflection(reactive). Absorption silencers would be very time consuming and expensive, and in the end you'll still need sound deadening material. So if you want down and dirty with best results. Buy exhaust blankets and FAE pipes. FreshairExhaust.com will make what you need. Our 6.0 inboard tige is so damn quiet you don't know the engines running....and this makes everybody happy. Wish I could post pictures???? Rorell.

http://www.freshairexhaust.com/
http://www.silex.com/pdfs/Exhaust%20Silencers.pdf