GM Performance 350/290 motor question

[Tomahawk30]

So I just found this thread as my 72 has the same engine w/ a similar carb (Quick Fuel HR-680) that I am trying to get tuned in. Where did you end up with your initial / total timing? Did you end up using your vacuum advance? How about your final accelerator pump nozzle size? Did you end up changing out your power valve too? Just trying to get a good idea of what worked for you.

I'm going through some similar issues, but I think I'm fighting a vacuum leak first. If I set my idle low enough that it is running only on the idle circuits, I have to set my timing no lower than about 14* BTDC and my vacuum bounces between 14 and 15 inHg. The previous owner (my father in law) had the 290hp Goodwrench engine installed, but they just reused the stock intake from the original engine. I'm using a squarebore adapter that I suspect is the culprit of the vacuum leak, but I might just buy an Edelbrock Performer like you used to install this weekend.

Any pointers about your setup that might save me a day (or an hour, or a few minutes) would be greatly appreciated!

Thanks!
Jake