Carb heat question - O-360

[MrNomad]

For the O-360, connection to the heat muff via a 2" scat tube seems to be the accepted method. However, NTSB Identification DEN99LA062 said it was insufficient.

I have the Vetterman system with dual mufflers and both sides have a heat muff which MUST be constantly vented. In other words, the muff on the pilot's side cannot dead end at the carb box stopping air flow when carb heat is not in use.

If a 2" aluminum flange in the form of a "Y" with a diverter valve was available, I could open the side to the carb box when carb heat was needed but send the hot air out the other side of the diverter when not needed.

Comments please. If this idea is not completely wacko, who sells a 2" aluminum "Y" diverter flange?

[L.Adamson]

I know the owner of that plane, have flown in it, but what I don't remember, is if it had the 2" scat tube mounted above an open flange for added airflow, such as newer kits have. It seems that the old models, allowed air from the 2" tube only.

And BTW, it's been re-built and flying again.