340 Initial timing questions

dont be afraid to run 30 initial?
Don't run any more at idle than you have to
be prepared for that batch of bad gas fill up out on the road/ hot weather. etc
as to the 34 suggestion TOTAL w/o Vac
works for most X-J 360 stock heads
later take less
once you quit improving back it down a notch and drive it
more advance past max power just makes additional heat and removes your margin of safety
lots of good ideas in this thread
glad that big cam works for you
not the way I'd do it but lots like that kind of build
your combo must work together well