On Sep 8, 1:33*pm, (Richard Casady) wrote:
On Mon, 8 Sep 2008 08:31:27 -0700 (PDT), wrote:
Normal IC aircraft engines aren't muffled, and the back pressure has
an affect on them if you try to.

Most, maybe all, of the planes I have experience with have had
mufflers. Includes radial engines from the thirties, and the usual
Piper, Beech, and Cessna planes in use from the forties on. Still
loud, every one of them.

Casady

From what loogie suggests, the engines may not run if muffled too
much. Is there ways to do it? Could these boats be made to be somewhat
sane? I know that with our bikes there are trick pipes that are very
loud, but several private tracks we frequent won't allow them. Guys
have to change pipes and rejet to ride there, but it can be done... I
don't think there is a lot of reason for a pleasure boat to be so
loud, although I do not have problems with loud vehicles in sanctioned
races, with proper permits and such...