An unmodified dissy with a worn limit pin has too much advance, too soon. Do not set the base timing higher than 7*BTDC.i'm using a stock, not recurved distributor. Ive been going back and forth with running the advance line to the outside or the inside diaphram on the vacuum advance. Initially I had the advance set at 7 degrees, with vac line to the inner primary advance port. It ran better when I ran the advancer line to the outer port. I then tried to advance timing to about 11 degrees and use the outer advance port, which it runs really well with no pinging, but I do get some dieseling on shutdown. Im thinking since I havent had a recurve that the outer secondary port on the dizzy helps limit total advance, but where would initial advance be best set at?