Right now my distributor has a bushing in it allowing 21 degrees advance. I'd set the total at 36 which would leave the initial at 15, or I could install a bushing allowing initial to fall back to 11. All advance is in by 2600rpm and I run a vacuum advance on the street. What would you use as a starting point for the ignition curve and any advice on where open chamber big blocks like to run at (total)? This is a 10.5 big block with open chamber heads and 37cc domes.Unfortunately I won't be able to tune this on a track or dyno this year, so I gotta ball park it off the seat of the pants and plug readings. Thanks.