71 Duster 360 turbo build

I have the cnc speed masters with 65cc chambers. Probably not very efficient. I’m mostly interested in the max N/A number as a starting point when it comes to pulling timing for boost. I’m assuming I would need to make some N/A pulls and check straps to get an accurate number?
That’s a pretty common cylinder head around here. You could probably poll the audience and come up with a good number. It’s a cnc closed chamber with a decent spark plug location. I’d bet that chamber wants 33-35 degrees max power timing NA.