[JCoop]

Try setting it with the vacuum DISCONNECTED to 34 max at 3500RPM. With the vac connected, it may yield up to 45 degrees at 3500 but that's without load. Also, the vac take-off for the dizzy should be hooked up to the carb base, or the proper port, depending on the carb, not the direct manifold port. You could also just run it without vacuum advance if you're emission exempt and don't care too much about a little loss in mpg. I had problems with a Weber setup and it boiled down to ignition timing to get a proper baseline. Very critical on small blocks, especially when you start upgrading the induction, I think. Your new carb may be setup too rich as well. What carb is it?

The other way is the old school way I was taught: keep dialing in advance until it pings, then back off a bit. Good luck and let us know how it goes.