Ignition or Fuel?

Green Hornet said

I've been having a fair share of issues with a new 408 build in my Dart. There is a miss and pop out of the exhaust starting at around 1800 RPM and continues up around 3200 and tapers off some. I pull the spark plugs and find that plugs 1-2 look like brand new, 3-4 have a little carbon on them and the porcelain is light brown, 5-6 are black, and 7-8 look more similiar to 3-4. Ignition is all new MP electronic with chrome box and new MSD Blaster coil. The carb is a fresh rebuilt Thermoquad. Any help would certainly be appreciated. Thanks!

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I once had this problem with a gold MP ignition box. It misfired like yours is.
The problem stumped all of usfor quite a while.
Turns out that the ignition module was mounted too close to the coil.
The high energy pulses from the coil were interfering with the low voltage signal to the module from the coil. Apparently there is what is called a 6 to 1 rule.Move the coil one inch away from the module is equivalent to 6 ft away.

In other words try to move the coil and the chrome box further away from each other and see if that solves your problem.

Duane