You may need to open it up a bit as you say. Maybe just a bit more behind the pitts; Something like Keith's install. I would concur with your assesment of the carby getting a bit hot and vaporizing the fuel prior to mixing and induction to the case.
Both of you have really clean installations. Would bet they get a lot of positive nods athe field. The pitts silencers really help a lot to keep the lines nice and you both took some care in cutting the cowls. You'd be amazed at some of the hack jobs I've seen on cowls at the field. Then again, maybe not
I don't care who you are(looking at them), anyone would have to say you both have some fine looking planes. (but then I'm biased...I always liked the Tony since building a Revell plastic model of it when I was a kid...metallic jade green spots with some kind of periwinkle interior and wells...yikes[&:])