Back it down to a point where you can get the engine to idle and still have plenty of screw to slow it down on the carb. Then advance the timing to the point where it starts to ping and back it down to the point where that stops .You want to run as much advance as you can and not have pre ignition pinging. You may also be off a tooth so re check that the dist is pointing at or just a hair before #1 wire at TDC The early slants like the 65's call for 5 before TDC I usually don't pay too much attention to the numbers.I do it to the max advance the engine will run good at because that's really where the engine wants to be.
