<VV> Single Carburetor-reply

[John Ingram]

Lon, Frank, Jim, and Joel,
Thank you all for your quick response!  If these setups are known to  
be weak in low end torque then that is the way it will be.  However,  
I've heard of adjustable vacuum canisters etc.  A little more  
explanation:  I've tried to get this worn and not too healthy engine  
to run on its 2 carburetors with some success and finally gave up  
after getting rebuilds that didn't solve the problem.  I don't blame  
the carburetors, the engine may have a crack or some other vacuum  
leak that I can't find it.  I live inside the Baltimore beltway so I  
normally drive from stoplight to stoplight.  No matter how much  
horsepower you have or want, the most important thing, in my opinion,  
is having a good idle.  Stalling out at stoplights is not good in a  
rat race.  The single carb does give a good idle.  The Rochester 2  
barrel came off a 67 Chevy 283 and I rebuilt it.
The problem is when I watch the vacuum advance when I blip the engine  
from idle it dips before it goes up, after that the advance is  
normal.  I have set the timing by making sure it does not go above 32  
degrees BTDC at high rpm.  I need to get rid of the "dip".  The  
engine sometimes stumbles when it dips and may even pop back through  
the carburetor. The vacuum is connected to the vacuum tube already on  
the carb, not from the manifold.  Would manifold vacuum work better?
JI