Just a question..
You mentioned you put in coils, did you put in new, oem coils? What about the ignitor? I know a lot guys use that ISR trash, but you get what you pay for, and companies like that factor in a certain percentage of crib death in their brand new parts.
Also, make sure all your grounds tied to the ignition/fuel system are as good as you can get them. The more stress you put on the engine once it's warmed up, the more it'll demand from those grounds, and they aren't up to snuff, things can get a little funky.
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