Just checked the manifold vacuum on my 440 with a Mopar 509 cam. I'm getting only about 5" at 1000 rpm, 4" or less at 800 rpm. This seems very low to me. I checked for vacuum leaks (carb cleaner method) but didn't find anything.

What do you guys think?

I'm concerned that my power valves may be opened up at such low vacuum levels. I'm able to turn the idle mix screws in almost all the way before killing the engine.

Just got the car this spring and have been chasing a "surging at cruise" issue since I've had it.

My timing is at 18 intial, 36 total. I've playing with this some to try in increase the vacuum level, but without any real success.