OK got a borrowed MSD box and coil wired in to run AB tests tomorrow at the test and tune.
Will update if I catch the gremlin and let you know what I found

My money is on the MSD. I had A digital 6 box that missed in high gear. I took it to the MSD trailer on drag week and they ran it through all kinds of tests and it passed, jumped spark like 4" on the test machine and they gave it the clear. I fixed it by changing to another digital 6 box. Fast forward two years and that box catches fire on drag week. I changed back to the original box and got my high gear miss back lol.

Had the same thing years ago. Intermittent miss in high gear. But would do it about every 3rd pass or so.
Chased it most of a summer. Ended up being the MSD box.

I agree w/ these guys...I bet it's the MSD box. The coil is probably fine so change one at the time. I've also had weird high speed misfire issues w/ the MSD digital boxes. That's why I'm still running the old style 6AL. Usually when they die, they just stop firing completely, but not always.

Pat Collins at TechWest Racing in NC repairs MSD products.
http://www.techwestracing.com/

Well did the AB test with the borrowed box first same issue, then tried the borrowed coil same issue, went back to the originals system and it cleaned up a bit but it was so hot out that I think
it may be a carb issue?,
Going to go back to a slick instead of the drag radial to take out one variable...best time in sig I found the air and it was about 900', im sure we were at 2500' or so today, search continues
Good thing is my daughter at the age of 17 is hooked and the Duster
is running pretty spot on at 12.90-13.00 and she is cutting pretty good lights, watch out Woodburn

How old are the plug and coil wires? I had a set of Accel Super Stock 8MM wires wear out on three wires on the passenger side, #4,6,and 8. It burnt the graphite coating off the nylon center conductor at the distributor cap back about a 1/2 inch into the wires with 90 degrees ends on that set. I found that out with a ohm meter, these where not the newer wires with the stainless wires wrapped wound the cores like sold today, it would start a intermetent miss around the 1000 Ft mark in high gear at night during eliminations, it ran fine in qualifying during the afternoon I cut the bad part off about 1/2 inch back and resued the ends and dust caps and it ran fine after that IHTHs
I can't believe your daughter is 17 now, it seems like she was 10 two years ago

Just yesterday I found a dead wire on a fairly potent SB Chevy and was hard to catch w/that choppy cam but found it w/an ohm meter.........

Wire are Firecores and maybe 2 years old with very minimal passes
I put an Ohm meter on the wires and then again thru the cap nothing seemed out of whack

Do you have a wideband and if so what does it show during this problem.........

I do have a FAST 2 sensor wide band that I may try this weekend

So you haven't used it yet then............

Is there any possibility of the ground for the whole system or power for the whole car varying? A loose(or almost loose) connection may cause trouble? As a last resort, you could put it on a chassis dyno and see what shows up, if they give the right readings? I found a slightly loose 12v+ connection to my MSD and command center, luckily it didn't mess things up.