Starving for air?

[SkiBoy]

My '99 Outback LS makes an odd noise now and then. I'm skiing and don't hear it, but it was described as a 'starving for air' sound by a mechanic friend. There is no loss of power or speed, no increase in engine temp, etc. When I let the engine cool by raising the cowling between runs, it does not make the sound. Also, when I put a small block under the cowling to let in additional air while skiing, the sound does not happen. I am thinking of putting closable vents in the front of the cowling like there is in the rear.

Anyone have similar airflow problems? I clean the spark arrestor twice a year. It's clean. I am having the carb rebuilt this winter. (600 hours)

My blower has malfunctioned since the beginning and does not work. (I lift the cowling to get fresh air in) I checked the intake hoses and there are no obstructions.

Thanks

[zabooda]

My 98 has a whooshing sound when the 4 barrel closes at about 37-38 mph when pulling back the throttle. You have air vents from the front and at least one vent going back connected to the blower and two small vents at the back of the engine cover.

[SkiBoy]

That isn't the sound they are hearing. This is a sustained sound when under power. I have not heard it, but it is not the sound that comes when you back off the throttle. Whenever I prop open the cowling, it does not happen. It seems the extra air coming in solves the problem.