Quiet it down!!

[Kurtis500]

I have a BBC with Nicson manifolds and the big aluminum risers with aluminum tips on the back of the boat. The tips had the rubber flappers over the edges until I ripped one off. Is there an exhaust tip on the rear that will help reduce noise? I noticed some are longer and point down or bevel the cut downwards. Any of you guys made an effort to quiet down your motors or engine compartments? What has worked well and what hasn't?
Thanks

[cdog]

I've got the Imco gatlins. I passed at the marina with a pretty large cam. The EFI helps town the engine down over a carb. It made my idle quality alot better so I passed the noise test.

[UBFJ #454]

Darren -
I have some questions about some carbon fiber work we're going to do ... Could you give me a call? (602) 234-1818.
Jak