manifold vaccum for vaccum advance ?'s

yes they are in the correct order. I tried a spare coil and t made the popping go away at an idle while on ported vaccum, but as soon as i put it on manifold vaccum the popping was back. The coil i was running checks out on primary resistance at 1.8 but secondary resistance was at 11.50k and its spos to be at 9.50k. I noticed the secondary resistance goes down as the coil cools off, i tested it about 15 minutes later and its at 10.45k.
My repair manual says the coil needs to be at 9.50k, i'm wondering if maybe thats why it was doing it, but i doubht it could b something that simple.