Re: insted of muffs
yes, i always tune my engines either in a drum or a trough/test tank all depends on where it will fit best. If yours fits in a drum (even if you have to unbolt a whale tail to do it) that is usually easiest. I prefer plastic drums over steel as they dont rust... and you can drill a plastic drum very near the bottom about 3/8" hole and simply thread a stainless bolt into it without tapping it so that it is easier to drain when your done. The only down side to the drum is that with any engine bigger than about 7.5hp you can empty the drum of water in a heartbeat by putting it in gear and opening the throttle... this is where a trough/test tank has an advantage. If you know where your engine sits in the water when your boat is at rest you can recreate the same back pressure with the drum by adjusting drum/water height to duplicate it.... the engine should run the same in drum as in lake.
err be carefull to make sure the water pump and intake are below the water line in the drum. and remember to add make up water as it is needed.
sean
