Stopping the knock: Lower compression and ported heads...

Frankenduster said

I read this and wondered if you left out something.
If I set the initial to anything less than 16 degrees, the idle suffered. If I ran the total up to around 30 degrees, the car knocked. I suppose that I may have been able to run the timing curve locked out but at what point would I set it ?

Click to expand...

Your experiments yielded a solution that did not have any audible issues: 6° initial, and 14° centrifugal. You said it didn't ping. Then you chose to have the heads ported and run special head gaskets. All you needed was to give the distributor some beyond-the-norm effort and the carb needed some further tuning to get rid of your idle issue. This could have been done without ever even changing the cam judging by the lower pressure from the first cam.

The solution was giving it more initial and less centrifical and slowing the rate of advance until you found what worked best, retuning the carb as you changed the timing. It would have taken a lot of finely detailed work and little cash for carb parts and gas. In terms of where to set it - there's over ten pages (and that's just on this board - not including the others you have threads on) of ideas, timing adjustment, setting, and rate of advance details, carb tuning details, and competing mechanical concepts helpful people added. Nothing has been left out.