Backfiring

http://uploads.tapatalk-cdn.com/2016...26c8447640.jpg
1 to 8 left to right. Thoughts?

1&5 look like they have more carbon/oil suggesting those cyl are either not firing or have a weaker spark

how many miles on the plugs?

Half a mile and idle. I'm replacing those two coils

1/2 mi, ouch

coil is suspect for those cyl. you could swap coils to another cyl to see if problem migrates to those cyl or just lay the plug against the head and crank motor to see if you get spark

but those two plugs never saw spark if they are that fouled in 1/2 mi of use

I literally drive it around the block twice and then let it idle

Replaced the two coils and new plugs.
Backfired as it cranked. Ran for about 20 seconds before it backfired again. It's backfiring out the intake again.
I'm going to go over the wiring again and see if I missed anything.

Also I should note it only seems to backfire at idle. Out of all the times it has done it I don't believe it has done it with the foot on the pedal.

If its a new coil and plugs, something is goofy with your wiring IMO.

I'll go over it again and I hope I messed up somewhere.

How aggressive is the new cam and how close is the tune?

No horrible vac leaks, or stuck injectors?