>Hector (friend of Lonnie) measured it and said it did not match what a 350 >vacuum should be. Said maybe there is a different cam on it (but I don't >think >so). Vaccum being off, the 3 deuce set-up has not been working. I >am >currently running on 1 carb.

Vacuum is affected primarily by cam timing and the induction/intake system. It can vary from what you'd see on a stock engine to less vacuum on engines with more radical cams. Those look like small base Rochester 2G's on your three duece set up. I'm assuming you're running some type of progressive mechanical linkage?

>I don't know enough about engines yet to know for sure, but by simple logic, it >seemed to me that possibly if the headers were restrictive it could create >some >kind of "pressure"...??

You're not completely off base with your reasoning regarding the exhaust/vacuum relationship. Extreme restriction in the exhaust system can prevent complete purging of exhaust gas from the cylinder on the exhaust stroke. Any residual exhaust gas left after the exhaust stroke will diminish the volume of intake charge on the intake stroke and thus affect vacuum.

Bob