The real reason I put one one was to 'encase' or shroud the carbs so that
the heat from the air cooling vent didn't waste the air all over the
place; it works, carbs are lukewarm.
Recent update from Kevin with pic.
503/582 twin carb with air-filter
box from Rotax gives:-
2.4 DeciBel sound reduction
No change in performance I can
detect despite smaller jetting
Warm carbs (they shroud the
carbs and gather the heat from the cowling)
No fuel leaking out of the
Mainair have it down as a
factory mod, so no paperwork thank God.
(Air Création fit them as
standard to the Fun Gt)
Photos enclosed, actually looks good in the flesh
Editor's note : I am nervous about
fitting one to my 582, as it would appear to block off the air flow to one
of the radiators - anyone who has successfully fitted one please let us
know how the temperatures behave.
I have measured the difference in sound
from the ground at 500 feet with an aircraft using an airbox and one
without and have found NO difference in the noise when using an air
box to just using an air filter.
To reduce noise - use a higher ratio reduction ratio, and spin a larger
multi-blade propeller slower.
Would you be able to hear one kid whispering in a
crowd of kids screaming? The air noise passing the aircraft in
flight, the exhaust, the prop are all louder than the noise from a
carburetor with an airfilter on it!