out of the exhaust

 

Uh, check your wire routing for one thing. They should all be in their clips, not overlapping and properly seperated, that's important. Cap and Rotor, take the cap off and look at how bad the contacts are. You may even see carbon traces where it is grounding out. These are the obvious things...not a computer. Also, take your coil off the block, clean the mating surfaces with sandpaper, and bolt it back on.

Ohh and I would like to know what you used for plugs. Brand and model number. If you say bosch, stop right there and take them back out for some copper autolites. Just regular plugs is all you need for these engines, I've had nothing but bad luck with platinums on the magnum.