Is the long block healthy? you might check cranking compression and leakdown. (basics never hurt). vac leak/mixture in ballpark/free flowing ex/unrestricted air cleaner. any changes or adjustments immediately preceding this? I would see what RPM the adv is all in & I would want 36 total for a good ballpark. You may have already posted on some of this. assuming the TDC is good, 2&1/4" CW on the dampener from the slit is 35.5 degrees.