Mystery Rochester FI intake duct

[SuperNovaSS]

I recently bought out a decent size Rochester FI collection. The collector was a long time customer of mine. He moved out of the country. Few years ago and a friend of his bought all his FI stuff to help him out. I bought the parts from the friend. The friend was fairly knowledgeable and told me he IDed this part as being rare and valuable but we were not able to find the application. He felt silly for not writing it down but here we are. Does anyone recognize this piece.

Thanks,

Jason