Thread: tuning with a vac gauge?

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I read the thread from earlier this month concerning ignition timing using a vacuum gauge and light. My question concerns the degrees of ignition advance. So here is the situation:
I finally got the SBC 350 back into my work truck. I put a small cam in it and brought the CR up a bit, but it is still intended to be just a solid reliable everyday driver of a 3/4 ton 4WD. I ran into some cooling issues last weekend, vapor lock maybe? So finally this week I have the thing fairly worked out and take it down the road. Timed at 0 deg it is an absolute waste of a truck. It is like a kid tripping over his shoelaces! So I ditched the factory specs and decided to try the vacuum gauge. I figure that it would be a direct reading of how the engine combo wants to be happy with itself. The vac topped out at 19" while advancing the ignition and I retarded it back down to 17". Then I checked the timing light and came up with 17 degrees advance. The truck runs much better but still doesn't start stretching its legs until after 35-40MPH. It also idles rather slowly in drive at the light. I am assuming that there is low vacuum at this point, most likely due to the cam timing and overlap.
Does this sound typical? I am questioning the cam timing, that maybe I should time it so that the intake closes sooner. This would increase cylinder pressure for more low end torque and also the load-idle vacuum as a side effect. I really want to get the most out of this engine but it is definitely just a working class truck.

btw. cam is comp 12-249-4 112deg/on 108 CL installed straight up. http://www.compcams.com/Technical/Se...umber=12-249-4 Static CR 9.5:1