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Hello folks, my coil is as follows:

12/60 NST
8 seriesed Victoreen spark gaps
safety gap
11.16 nF EMMC
.25" Cu tubing .4" spacing, 15 total turns, flat pancake
16" of 22AWG on 4" PVC

My previous toroid was aluminum ducting, 4" diameter, 16"
center-to-center.  With this, coil tuned at about 7.2 turns and I got
about 2' or a little of output.  No problems with downward strikes at
all, and no racing sparks.  I just made and tried out a 6" diameter, 18"
center-to-center toroid instead.  I tried retuning at 9 turns and got
massive racing sparks.  I even raised the toroid about 3" more than the
old one and still the same.  Where am I screwing up?