I'm sure that Schornack curved your distributor for performance. You will have to decide whether you want the performance or not. One cool thing about sending out a distributor to Schornack is they test it extensively before they send it back to you. That's what you paid for. Chances are you aren't going to inprove on it by swapping out springs at this point. If you told Schornack exactly what your engine specs are/were then you most likely have the perfect curve already.
Try a little racing fuel Doug. I bet the pinging goes away. You will also be very happy with the added performance. If you want to burn 92 or 93 in a 10-1 engine then you better use aluminum heads. You said you read the other thread where Rommel worked on his distributor to get rid of the ping. Rommel's engine runs 9.5-1. You can't compare it to your 10-1. I thought it might simply be a octane versus compression problem. Turns out that's exactly what it is! Anyone doubting this should really read that old thread that was (ironically) started by Doug a year ago. Here's that link again; /forums/ubbthreads.php?ubb=showflat&Number=45785&page=0&fpart=1