Hi Bill,

First of all thank you for being so polite about not naming the vendor who restored your carbs (me), I appreciate it.

As I mentioned to you before in our emails back and forth, it does sound like a vacuum leak to me, 10 inches of vacuum is quite low for a stockish Hemi, mid to high teens would be the norm. I can't diagnose your engine from here but I would look very hard at your timing (distributor and vacuum advance in particular) as well as your carb base gaskets and the intake manifold seal (not an easy one).

Hemi carburetors are pretty simple and not usually a source for a vacuum leak, plus they ran fine on the test engine before shipping to you. That said after you do your checking and you feel it might be the carbs please feel free to return them and I'll give them a thorough checking over at no charge.

Thank you for your business!
Scott